Question

what is the surface area of a sphere with diameter 6 cm?
○ 113 cm squared
○ 57 cm squared
○ 38 cm squared

Explanation:

Step1: Find the radius

The diameter is 6 cm, so the radius \( r = \frac{d}{2} = \frac{6}{2} = 3 \) cm.

Step2: Use the surface area formula for a sphere

The formula for the surface area of a sphere is \( SA = 4\pi r^2 \). Substitute \( r = 3 \) into the formula:
\( SA = 4\pi(3)^2 = 4\pi\times9 = 36\pi \).
Using \( \pi \approx 3.14 \), we get \( 36\times3.14 = 113.04 \approx 113 \) \( \text{cm}^2 \).

Answer:

113 cm squared