Answer:
A is true.......................b is false....................and c is false
Step-by-step explanation:
Answer:

Step-by-step explanation:
To make this a bit easier to see, we'll expand that expression.
R to the 9th is just r times itself 9 times. R to the third is r times itself 3 times.
(excuse my bad formatting)
<u>The expression:</u>
<u>r • r • r • r • r • r • r • r • r • 1</u>
r • r • r • 1
Remember, anything and everything has a coefficient or denominator of 1.
So, we can cancel 3 r's from the numerator and denominator.
<u>r • r • r • r • r • r • 1</u>
1
Simplify....

That just equals
.
Answer:
D. She used the beach's ball's diameter when she should have used the radius
Step-by-step explanation:
To find the volume of the beach ball, using the volume of a sphere is the right formula to use, which is ⁴/3πr³.
The formula she used is correct.
Since the diameter of the ball is assumed to be 12 inches, what is needed to find the volume is the radius.
Radius (r) = ½(diameter) = ½(12) = 6 in.
This is where Emily made a mistake.
She used the diameter of the beach ball instead of its radius (r) which is needed in the equation.
She should have gotten,
V = ⁴/3(3.14)(6)² = 904.32 cubic inches
One rotation has 360 degrees. Since regular Pentagon has 5 sides and each of them takes 360/5=72 degrees when looked from center, if we rotate regular Pentagon by 72 degrees we will get same shape as we started from.
Therefore answer is 72 degrees.