Question

pls help

What is the length of the radius of a sphere with a diameter of 12 cm?(1 point)

Answer 1

Find the surface area of a sphere with a diameter of 40 inches. Leave your answer in terms of pi.
(1 point)

Answer 2

Find the surface area of a sphere with a radius of 3.6 ft. Use 3.14 for pi. Round your answer to the
nearest hundredth, if necessary.(1 point)

Answer 3

The radius of a sphere is half of its diameter. Given that the diameter of the sphere is 12 cm, the radius can be calculated as:

\[
\text{Radius} = \frac{\text{Diameter}}{2} = \frac{12 \text{ cm}}{2} = 6 \text{ cm}
\]

So, the length of the radius of the sphere is 6 cm.

Answer 4

To find the surface area \( A \) of a sphere, you can use the formula:

\[
A = 4\pi r^2
\]

where \( r \) is the radius of the sphere.

First, calculate the radius from the diameter:

\[
r = \frac{\text{Diameter}}{2} = \frac{40 \text{ inches}}{2} = 20 \text{ inches}
\]

Now, substitute the radius into the surface area formula:

\[
A = 4\pi (20 \text{ inches})^2
\]
\[
A = 4\pi (400 \text{ inches}^2)
\]
\[
A = 1600\pi \text{ inches}^2
\]

Therefore, the surface area of the sphere, in terms of pi, is \( 1600\pi \text{ inches}^2 \).

Answer 5

To find the surface area \( A \) of a sphere, you can use the formula:

\[
A = 4\pi r^2
\]

Given that the radius \( r \) is 3.6 ft, we can substitute this value into the formula. Using \( \pi \approx 3.14 \):

\[
A = 4 \times 3.14 \times (3.6 \text{ ft})^2
\]

First, calculate \( (3.6 \text{ ft})^2 \):

\[
(3.6 \text{ ft})^2 = 12.96 \text{ ft}^2
\]

Now, plug this value into the surface area formula:

\[
A = 4 \times 3.14 \times 12.96
\]

Now perform the multiplication:

\[
A \approx 4 \times 3.14 \times 12.96 \approx 4 \times 40.7904 \approx 163.1616
\]

Rounding to the nearest hundredth:

\[
A \approx 163.16 \text{ ft}^2
\]

Thus, the surface area of the sphere is approximately **163.16 ft²**.