18 inch diameter = 9 inch radius
Sphere Volume = <span> 4/3 • <span>π <span>• r³
</span></span></span><span>Sphere Volume = <span> 4/3 * PI * 9^3
</span></span><span>Sphere Volume = <span> 4/3 * PI * 729
</span></span><span><span>Sphere Volume = </span>3,053.628 </span>
By using the process of elimination, the answer is A.
Given
Area of the regular pentagon is 6.9 cm².
Find out the perimeter of a regular pentagon
To proof
Formula
Area of regular pentagon is

As given in the question
area of regular pentagon = 6.9 cm²
now equating the area value with the area formula.

Now put
√5 = 2.24 ( approx)
put in the above equation

thus
a² = 4.01
a = √ 4.01
a = 2.0 cm ( approx)
As perimeter represented the sum of all sides.
i.e regular pentagon have five sides of equal length.
Thus
perimeter of the regular pentagon = 5 × side length
= 5 ×2.00
therefore the perimeter of the regular pentagon = 10cm
option c is correct
Hence proved
Ans5
Step-by-step explanation:
5