Question

what is the surface area of this sphere?
round your answer to the nearest hundredth.
19 mm
____ square millimeters

Explanation:

Step1: Recall sphere surface area formula

The formula for the surface area of a sphere is $SA = 4\pi r^2$, where $r$ is the radius.

Step2: Substitute radius value

Here, $r = 19$ mm. Substitute into the formula:
$SA = 4\pi (19)^2$

Step3: Calculate the squared radius

First compute $19^2 = 361$, so:
$SA = 4\pi \times 361$

Step4: Multiply constants

$4 \times 361 = 1444$, so:
$SA = 1444\pi$

Step5: Compute decimal value and round

Use $\pi \approx 3.14159$:
$SA \approx 1444 \times 3.14159 \approx 4536.45596$
Round to the nearest hundredth: $4536.46$

Answer:

4536.46 square millimeters