when she got to school she saw that the school has nine buildings each having 30 classrooms how many classrooms does the school have

Answers

Answer 1
The school has 270 classrooms, hope this helps.
9(30) = 270
Answer 2
The answer is 9 * 30 = 270

Related Questions

In the number 7,889 which contains digits where one digit is ten times the value as the other digit?

Answers

U have to the 8 the ones and the 9 the tens

Solve for a.

a+(−4)=−13

What is the answer?


a=−17

a=−9

a = 9

a = 17

Answers

The answer has to be -9 because -9 + -4 is equal to -9 - 4, and that equals -13. 
The answer is B because-
-9 + -4 = -13
-13 = -13

A is not the answer because- 
-17 + -4 = -13 
-21 ≠ -13

C is not the answer because- 
9 + -4 = -13
5 ≠ -13

D is not the answer because- 
17 + -4 = -13 
13 ≠ -13


What is the value of mc020-1.jpg?
40
77
4,096
9,317

Answers

Answer:

The answer is 77

just took the test ;)


The value of the function (f/g) (5)  is 270.

What is a function?

A relation is a function if it has only One y-value for each x-value.

The given functions are f(x)=7+4x

g(x) = 1/2x

We need to find the value of f/g(5)

(f/g) (x) = f (x)/g(x)

(f/g) (5) = f (5) / g(5)

Now we will put the value of x = 5

f (5) = 7 + 4 (5) = 27

g (5) = 1 / (2)(5) = 1/10

(f/g) (5) = 27 / (1/10)

(f/g) (5) = 270

Hence, the value of the function (f/g) (5)  is 270.

To learn more on Functions click:

https://brainly.com/question/21145944

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The given question is not complete.

The question will be like this, the function f(x)=7+4x, g(x) = 1/2x  then value of f/g(5)?

The volume of a rectangular prism is (x4 + 4x3 + 3x2 + 8x + 4), and the area of its base is (x3 + 3x2 + 8). If the volume of a rectangular prism is the product of its base area and height, what is the height of the prism?

Answers

Dividing the volume by the base area, you find the height to be ...
[tex] \frac{x^{4}+4x^{3}+3x^{2}+8x+4}{x^{3}+3x^{2}+8}=x+1-\frac{4}{x^{3}+3x^{2}+8}[/tex]

The height of the prism is [tex]x+1-\frac{4}{x^{3}+3x^{2}+8}[/tex]

If the volume of a rectangular prism is the product of its base area and height, than the height of the prism is given by:

[tex]h = (x+1)-\dfrac{4}{(x^3+3x^2+8)}[/tex]

Given :

Volume of rectangular prism [tex]= x^4+4x^3+3x^2+8x+4[/tex]

Base Area of a rectangular prism = [tex]x^3+3x^2+8[/tex]

[tex]\rm Volume = Base \;Area\times Height[/tex]  ---- (1)

Solution :

The volume of prism is the amount of space a prism occupies. It has two same faces and other faces that resemble a parallelogram.

Let the height of the prism be h.

Now, substitute the value of base area and volume of the rectangular prism in the given equation (1).

[tex](x^4+4x^3+3x^2+8x+4) = (x^3+3x^2+8)\times h[/tex]

[tex]\dfrac{x^4+4x^3+3x^2+8x+4}{x^3+3x^2+8}=h[/tex]

[tex]h = \dfrac{((x+1)(x^3+3x^2+8)-4)}{(x^3+3x^2+8)}[/tex]

[tex]h = (x+1)-\dfrac{4}{(x^3+3x^2+8)}[/tex]

If the volume of a rectangular prism is the product of its base area and height, than the height of the prism is given by:

[tex]h = (x+1)-\dfrac{4}{(x^3+3x^2+8)}[/tex]

For more information, refer the link given below

https://brainly.com/question/15861918

The area of a circle is represented by the following expression, where r is the radius of the circle.



Find the approximate area of a circular pool cover with a radius of 12.5 meters. Use 3.14 for .

Answers

To find the area of a circle you need to multiply the radius times pie times 2

What is the volume of a cube with a side length that measures 8cm? ANWSER ASAP please

Answers

what you do is 8 x 8 x 8 and cube your number 
=512
v=512cm3 if tell me if this works your wellcome

the points (10, 6) and (7, u) fall on a line with a slope of -4/3. what is the value of u?

Answers

Answer:
u = 10

Explanation:
slope can be calculated using the following rule:
slope = (y2-y1) / (x2-x1)

We are given:
slope = -4/3
point (10,6) representing (x1,y1)
point (7,u) representing (x2,y2)

Substitute with the givens in the above rule and solve for u as follows:
slope = (y2-y1) / (x2-x1)
-4/3 = (u-6) / (7-10)
-4/3 = (u-6) / (-3)
-3 * -4 = 3 * (u-6)
4 = u - 6
u = 4 + 6
u = 10

Hope this helps :)

A card was selected at random from a standard deck of cards. The suit of the card was recorded, and then the card was put back in the deck. The table shows the results after 40 trials. What is the relative frequency of selecting a heart? a:15% b:25% c:27% d:35% Outcome Club Diamond Heart Spade Number of trials 8 12 14 6

Answers

C.35%
If you divide the number of hearts drawn by the number of total draws you get your answer.

14/20=0.35

Ian is going to water his plants is it reasonable to say he will fill the watering can with 3 liters of water explain

Answers

This is possible for a smaller watering can. 3 liters is about 3/4 of a gallon (imagine a jug of milk).

It is equivalent to 3000 ml, which would also be 100 ounces of water.(5 -20 oz bottles of water).

Final answer:

It is reasonable for Ian to fill a watering can with 3 liters of water for watering plants, as it falls within the typical range required by houseplants and should suffice for watering multiple indoor plants or a small garden.

Explanation:

To determine if it is reasonable for Ian to fill a watering can with 3 liters of water to water his plants, we should consider the capacity of common watering cans and the typical water requirements for houseplants. For example, a standard watering can might hold anywhere from 1 to 10 liters of water, and most indoor plants generally require between 0.25 and 1 liter of water per week, depending on their size and the environmental conditions.

If Ian has several plants or a few large plants, 3 liters of water might be a perfectly reasonable amount for him to use. Without knowing the exact number and size of the plants, it is difficult to provide a precise answer, but in general, 3 liters is within a normal range for watering multiple houseplants.

For a substantial garden or larger outdoor plants, 3 liters might even be on the lower end, and multiple trips to the tap may be necessary. Thus, it is indeed reasonable to say that Ian will fill the watering can with 3 liters of water for watering plants.

What is 6.877 rounded to the nearest whole number

Answers

It is 7, because you always have to round up if the next decimal is greater than or equal to 5 (depending on where you live). 
Hello,

Here is your answer:

The proper answer to this question is "7".

Here is how:

Looking at the number closest to the whole number (6&8) you will see that 8 is bigger than 5 therefore it rounds up!

6.877=7

Your answer is 7.

If you need anymore help feel free to ask me!

Hope this helps!

-6x+6y=6
-6x+3y=-12

Solve using elimination

Answers

-6x + 6y =6
-6x + 3y = -12
You would multiply the bottom equation by -1 to make -6x a positive so you can eliminate it.
-6x + 6y = 6
 6x + -3y = 12
Eliminate -6y and add 6y to -3y as well as 6 and 12.
0 +  3y = 18
3y = 18
divide both sides by 3
y = 6 
 
now that you know the value of y it will be easy to find x :)




-6x + 6y = 6
-6x + 3y = -12

✨ You need to eliminate a variable, so I'll use -1 to multiply the first equation by.

6x - 6y = -6
-6x + 3y = -12

-3y = -18

✨ y = 6

6x - 36 = -6

6x = 30

✨ x = 5

✨ The solution is (5,6) ✨

∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘∘

♡´・ᴗ・`♡вяαιиℓιєѕт ρℓєαѕє♡´・ᴗ・`♡

rectangles. Please help!

Answers

First you have to canceled out the fours from both side 4x/4-12/4 so x=3 then you do the same thing to the 7x-18

4x-12.
4x/4-12/4. So x=3
The fours cancelled out

7x-18
7x/7-18/7. So x= 2 4/7
The sevens cancelled out

For f(x)=3x-1 find the average rate of change on the interval [0,3]

Answers

For a linear function, the average rate of change is the same everywhere. It is the slope of the function, the x-coefficient.

The average rate of change is 3.

_____
(f(3) -f(0))/(3 -0) = (8 -(-1))/3 = 9/3 = 3
The average change is 3

Matias stacked his cubes to make this rectangular prism. rectangular prism with grid lines How many cubes did Matias use?


https://static.k12.com/calms_media/media/1451000_1451500/1451333/1/fa05fd502d1273bf0751cb02832848aa1b938634/Math_Purple_140218_131628.jpg

Answers

Counting each visible cube, and multiplying it by 2, he used 112. If you counted them, there would be 56 cubes. You'd multiply by 2 for the non-visible ones.

Answer:

The answer is 112

Officials in a town use a function c to analyze traffic patterns. C(n) represents the rate of traffic through an intersection where n is the number of observed vehicles in a specified time interval. What would be the most appropriate Damian for the function

Answers

Answer: The domain of the function should be whole numbers.

This functions counts the number of cars that pass through an intersection as the domain (or input). Therefore, we would start counting at 0 and go up for each car.

The set of numbers {0, 1, 2, 3, 4, 5, 6, 7 ....} are called the whole numbers.

The most appropriate domain for [tex]\( C(n) \)[/tex] is non-negative integers, representing the count of vehicles observed.

The most appropriate domain for the function [tex]\( C(n) \)[/tex], which represents the rate of traffic through an intersection based on the number of observed vehicles [tex]\( n \)[/tex] in a specified time interval, would be all non-negative integers. This is because the number of vehicles observed [tex](\( n \))[/tex] can only be a whole number (you can't have a fraction of a vehicle), and it can't be negative.

So, the domain of [tex]\( C(n) \)[/tex] would be:

[tex]\[ \text{Domain: } n \in \{0, 1, 2, 3, \ldots\} \][/tex]

This means [tex]\( n \)[/tex] is any non-negative integer.

Two congruent triangles fit together to form a parallelogram with a base of 14 inches and a height of 10 inches. What is the area of each triangle?

Answers

To find the answer you will find the area of the parallelogram by multpltig the base (14 in) by the height (10 in).

After this you will divide the answer of 140 square inches by 2 because the area each congruent triangle would be half of the total area.

The answer is 70 square inches for each triangle.

Final answer:

The area of each triangle is 140 square inches.

Explanation:

The area of a triangle is given by the formula A = ½ × base × height.

In this case, the base of the parallelogram is 14 inches and the height is 10 inches.

Since two congruent triangles form the parallelogram, we can consider one of the triangles.

Let's call the base of the triangle 'b' and the height 'h'.

We have the equation A = ½ × b × h = 14 × 10 = 140 square inches.

Therefore, the area of each triangle is 140 square inches.

How is the square root of 343 cubed 7?

Answers

The square root of 343 is cubed 7 because 7x7x7 = 343
hope this helps
I don't know what your question means, but 7 cubed is 343, so the cubic root of 343 is 7.

[tex] 7^3 = 343 [/tex]

[tex] \sqrt[3]{343} = 7 [/tex]

Exponent and root are inverse operations.
If you square 5 to get 25, then when you take the square root of 25 you get 5.
7^3 = 343, so the cubic root of 343 is 7.


Question number 7 please

Answers

Hello,

I would be happy to help.

For Part A, you just count the number of terms, there are 3. So, it is a trinomial.

For Part B, you look at the highest exponent value, it is 2. So it is a second degree polynomial.

For Part C, you have to sub in the values for each year. You are looking for the number of years since 1930, so subtract 1930 from each year.

2020 - 1930 = 90
2030 - 1930 = 100

Then, sub in those values into the given expression to find the density.

0.005(90)^2 - 0.127(90) + 1 = 30.07
0.005(100)^2 - 0.127(100) + 1 = 38.3

Remember to use the order of operations!

Good luck,
MrEQ

1) Given the data 12, 39, 21, 18, 24, 17, 12, 25:
What is the outlier in the data?
What is the mean with the outlier?
What is the mean without the outlier?

A)12; 21; 18.4

B)12; 18.4; 21

C)39; 21; 18.4

D)39; 18.4; 21

Answers

In this data set, the outlier is 39 because it's value is not close to any of the other values.

The mean with the outlier is 12+12+17+18+21+24+25+39 = 168
     168/8 = 21

The mean without the outlier is 12+12+17+18+21+24+25=129
129/7 = 18.4

These are choice C.

match the math sentence that count on and back by tens.
38+20=? 63+40=? 42+30=?
77-30=? 53-40=? 91-20=?

Answers

38+20= thirty-eight, forty eight, fifty eight.
63+40= sixty-three, seventy-three, eighty-three, ninety-three, one-hundred three
42+30=forty-two, fifty-two, sixty-two, seventy-two, eighty-two.77-30= Seventy-seven sixty-seven, fifty-seven, forty-seven 53-40=fifty-three, forty-three, thirty-three, twenty-three, thirteen
91-20= Ninety-one, eighty-one, seventy-one
This method is where you count up and down by tens.

- ( 38 + 20 = 58 ): Counting 20 more than 38 gives 58.

- ( 63 + 40 = 103 ): Adding 40 to 63 results in 103.

- ( 42 + 30 = 72 ): Adding 30 to 42 gives 72.

- ( 77 - 30 = 47 ): Subtracting 30 from 77 results in 47.

- ( 53 - 40 = 13 ): Subtracting 40 from 53 gives 13.

- ( 91 - 20 = 71 ): Subtracting 20 from 91 results in 71.

let's go through each math sentence and solve them step by step:

1. ( 38 + 20 )

  - Start with 38.

  - Add 20 to 38.

  - Calculation: ( 38 + 20 = 58 )

  - So, ( 38 + 20 = 58 )

2. ( 63 + 40 )

  - Start with 63.

  - Add 40 to 63.

  - Calculation: ( 63 + 40 = 103 )

  - So, ( 63 + 40 = 103 )

3. ( 42 + 30 )

  - Start with 42.

  - Add 30 to 42.

  - Calculation: ( 42 + 30 = 72 )

  - So, ( 42 + 30 = 72 )

4. ( 77 - 30 )

  - Start with 77.

  - Subtract 30 from 77.

  - Calculation: ( 77 - 30 = 47 )

  - So, ( 77 - 30 = 47 )

5. ( 53 - 40 )

  - Start with 53.

  - Subtract 40 from 53.

  - Calculation: ( 53 - 40 = 13 )

  - So, ( 53 - 40 = 13 )

6. ( 91 - 20 )

  - Start with 91.

  - Subtract 20 from 91.

  - Calculation: ( 91 - 20 = 71 )

  - So, ( 91 - 20 = 71 )

Therefore, the solutions are:

- ( 38 + 20 = 58 )

- ( 63 + 40 = 103 )

- ( 42 + 30 = 72 )

- ( 77 - 30 = 47 )

- ( 53 - 40 = 13 )

- ( 91 - 20 = 71 )

What is the mean for 43005,43007,43006,43005,43007

Answers

The mean would be 43006.

To find the mean, you simply add up all of the numbers in the sequence and divide by how many numbers are in the sequence.

 43005+43007+43006+43005+43007=215030

215030 / 5 = 43006.
Answer: 43006

To find the mean:
1. Add all the numbers up
2. Divide the sum of the numbers by how many numbers there are

43005 + 43007 + 43006 + 43005 + 43007 = 215030 
215030 ÷ 5 = 43006

at a local animal shelter there are 12 small size dogs and 5 medium sized dogs everyday the small sized dogs are each given 12.5 oz of dry food and the medium sized dogs are each given 18 oz of the same dry food how many pounds of dry food does the shelter serve in one day

Answers

12*12.5=150 oz 18*5=90 oz 150+90=240 convert to pounds = 15 pounds

The shelter serves a total of 15 pounds of dry food per day, after calculating the food given to both small and medium-sized dogs and converting the total from ounces to pounds.

To calculate the total amount of dry food served at the shelter in one day, you must multiply the amount of food each dog consumes by the number of dogs of that size. Then, add the totals for each size category. Since the pound is the most suitable unit for this calculation, you need to convert the ounces of food into pounds. There are 16 ounces in one pound.

First, calculate the total food for small-sized dogs: 12 dogs × 12.5 oz each = 150 oz.Then, calculate the total food for medium-sized dogs: 5 dogs × 18 oz each = 90 oz.Combine the amounts: 150 oz + 90 oz = 240 oz of dry food total.Finally, convert ounces to pounds: 240 oz ÷ 16 oz per pound = 15 pounds of dry food.

Therefore, the shelter serves a total of 15 pounds of dry food in one day.

* 20 points when marked brainliest *

Please explain thoroughly.

Answers

The formula for the distance (d) from point (x, y) to the line ax +by +c = 0 is
.. d = |ax +by +c|/√(a^2 +b^2)

The general form equation for your line is
.. x -y +4 = 0
so the distance to (4, -2) is
.. d = |4 -(-2) +4|/√(1^2 +(-1)^2) = 10/√2 = 5√2
.. d ≈ 7.1 . . . . . . . . . . corresponds to selection A

A group of seventh and eighth graders were asked whether they prefer reading fiction or nonfiction.

This table shows the relative frequencies of the rows for the two-way table representing this situation.

Select from the drop-down menus to complete the statement.

The percent of seventh graders surveyed who prefer fiction is ____ the percent of eighth graders surveyed who prefer fiction.

A. greater than
B. less than
C. equal to

Answers

7th graders prefer fiction is 0.75 = 75%
8th graders prefer fiction is 0.68 = 68%
7th graders is greater than 8 graders

answer
A. greater than

Answer:

Option A. greater than

Step-by-step explanation:

The percent of seventh graders surveyed who preferred fiction = 0.75 or 75%

The percent of eight graders surveyed who preferred fiction = 0.68 or 68%

Now we can say the percentage of seventh graders who preferred fiction is GREATER THAN the percentage of eight graders who preferred fiction.

Therefore option A. is the correct option.

If the dimensions of a square pyramid are measured in meters, then the surface area of the pyramid is measured in
meters
square meters
cubic meters

Answers

if the dimensions of the square pyramid are in meters, the surface area can be calculated as follows;
Surface area = area of square base + area of lateral faces 
                      = (side length of square )² + (1/2 * slant height* perimeter)
If we substitute the equations with the units of the dimensions 
area               = (meters)² + (1/2* meters * meters)
                      = m² + m²
total area       = m²
therefore the area is obtained in square meters (m²)

Answer:

If the measurments are in meters, then the surface area of the pyramid will be in square meters.

Step-by-step explanation:

Help meeeeeeeeeeeeee

Answers

You can just use the Pythagorean theorem if you're stuck, you know.

its a^2 + b^2 = c^2 where a and b are the short sides, or the legs, and c is the hypotenuse, or the long side.

How would 5,682,850,003 be written in expanded form?

A. 5 x 1,000,000,000 + 6 x 100,000,000 + 8 x 10,000,000 + 2 x 1,000,000 + 8 x 100,000 + 5 x 10,000 + 3 x 1
B. 5 x 1,000,000,000 + 6 x 100,000,000 + 8 x 10,000,000 + 2 x 1,000,000 + 8 x 100,000 + 5 x 10,000 + 3 x 10
C. 5 x 1,000,000,000 + 6 x 100,000,000 + 8 x 10,000,000 + 2 x 1,000,000 + 8 x 100,000 + 5 x 1,000 + 3 x 1
D. 5 x 1,000,000,000 + 6 x 100,000,000 + 8 x 10,000,000 + 2 x 1,000,000 + 8 x 100,000 + 5 x 100 + 3 x 1

Answers

I am pretty sure a is the correct answer

It would be (5 x 1,000,000,000) +
(6 x 100,000,000) + (8 x 10,000,000)
+ (2 x 1,000,000) + (8 x 100,000) +
(5 x 10,000) + (3 x 1)

Hope this helped!! :D

Mentone, Indiana claims to have the wor d's largest egg sculpture. A 5 foot tall person standing next to the egg sculpture casts a shadow that is 3 feet long. if the egg casts a shadow that is 6 feet long, how tall is the sculpture?

Answers

If the shadow is for the person that is 5 foot is 3 and the shadow for the egg is 6 it's going to be 10 foot bc it is double the height of the person shadow
10 Foot Tall 
Because if a 5 foot tall person casts a 3 foot long shadow then a 6 foot shadow would = 10 feet

$27.99 shoes ; 7 1/2 tax find the total cost or sale price to the nearest cent

Answers

27.99x.075= 2.09925 or 2.10 Rounded
27.99+2.10= $30.09

Answer:

$The total cost or sale price  = $30.09

Step-by-step explanation:

The total cost or sale price is the absolute price of a commodity including the given tax.

From the question given, the tax is [tex]7\frac{1}{2}[/tex]% of the price. So that;

Tax = [tex]7\frac{1}{2}[/tex]% × 27.99

      = 0.075 × 27.99

      = 2.09925

∴ Tax  = $2.09925

The total cost or sale price = price + tax

                                             = $27.99 + $2.09925

                                            = $30.08925

The total cost or sale price  = $30.09

what is the probability of randomly choosing a day of the week that dosen't begin with the letter t and the letter s

Answers

(S) (M) (T) (W) (T) (F) (S) = 3/7
3/7 there are 7 days of the week and three don't start with T or S
Other Questions
which president the oldest candidate ever elected push for large tax cuts for wealthy and attempt to stimulate economic growth for all When 1.640 g of titanium is combusted in a bomb calorimeter, the temperature of the calorimeter increases from 25.00 c to 76.50 c. in a separate experiment, the heat capacity of the calorimeter is measured to be 9.84 kj/k. the heat of reaction for the combustion of a mole of ti in this calorimeter is ________ kj/mol? All teens eventually move into kohlberg's postconventional stage of moral reasoning. a. True b. False According to the endosymbiotic hypothesis why did the large cell not destroy the small aerobic cell they engulfed In a region, there is a 0.95 probability chance that a randomly selected person of the population has brown eyes. Assume 13 people are randomly selected. Find the probability that the number of selected people that have brown eyes is 11 or more. You and your friend are standing back-to-back. Your friend runs 10 feet forward and then 8 feet right. At the same time, you run 11 feet forward and then 12 feet right. You stop and throw a baseball to your friend, who catches it. How far did you throw the baseball? Which of the following statements best explains why workers began to form unions? a The introduction of immigrant labor was more likely to raise workplace standards. b A united workforce was more likely to bring about changes in the workplace. c The introduction of unions was more likely to offer workers training in using newer technology. d A well-organized system of workers was more likely to maximize profits. Which of the following would be an advantage of living in a segregated community?A. safetyB. more choicesC. less competitionD. better education __________, the study of mapmaking, has been important for human navigation around the Earth. A. Geography B. Cartography C. Human geography D. Physical geography _____ refers to firms selling the right to use some aspect of their production processes, trademarks, or patents to individuals or firms in foreign markets In which category does this word belong? Assonance. A)part of a narrative. B) literary device. C) type of narrative. D) sound pattern According to vygotsky, children master activities through __________.a. operant conditioning and modelingb. joint activities with more mature members of their societyc. interaction with the physical environmentd. trial and error Which of the following is an example of a disease that is properly matched with one of its environmental risk factors? Hypertensionparents' genes Arteriosclerosisfamily history Hemophiliapoor nutrition Anemiairon-deficient diet, A poker hand consist of 5 cards?a.find the total number of possible five card poker card hands.b.find the number of ways in which one can king can be selected? c)find the number of ways in which four aces can be selected .d.find the number of ways of getting four aces and one king. The chemical formula for lithium phosphide is Li3P. Which best describes this ionic compound? PLEASE HELP ASAP!!!!The image is an energy pyramid for a particular food chain. The amount of energy received by the macaws will be ______.1. 56,000 Cal2. 560,000 Cal3. 560 Cal Macaws are captured and kept as pets. If the number of macaws decreases because of excess capture, the amount of energy received by the ocelots will be ______.1. More than 5,600 Cal2. Less than 5,600 Cal3. Equal to 5,600 Cal Around 1000, the _____________ established a city called, ___________________ in what is now zimbabwe in southern africa. this city became the capital of a gold thriving area Read the following sentence, changing the verb from the present tense to the preterite tense. Put the preterite form of the verb in the answer blank. Nosotros sabemos la verdad. (3 points) hElP!A carpenter designs two cabinets: one in the shape of an oblique rectangular prism and one in the shape of a right rectangular prism. The volume of each cabinet is 4,608 cubic inches. The oblique rectangular prism is 48 inches tall and has an edge length of 64 inches. The right rectangular prism has a height of 48 inches. Which statements about the cabinets are true? CHECK ALL THAT APPLYa. The cabinets have the same base area.b.The base area of the oblique prism is smaller than the base area of the right prism.c.The cabinets may have the same base dimensions.(MORE DOWN BELOW), Why is the idea of climate change controversial?