Calculate the surface area of the closed cylinder if the radius is 2 inches and the height is 5 inches.

image
A.
10π
inches
2

B.
20π
inches
2

C.
24π
inches
2

D.
28π
inches
2

1 answer

To calculate the surface area of a closed cylinder, we use the formula:

\[ \text{Surface Area} = 2\pi r(h + r) \]

where:

  • \( r \) is the radius of the cylinder,
  • \( h \) is the height of the cylinder.

Given:

  • \( r = 2 \) inches,
  • \( h = 5 \) inches.

Now we can substitute these values into the formula:

\[ \text{Surface Area} = 2\pi(2)(5 + 2) \]

Calculating the height plus radius:

\[ 5 + 2 = 7 \]

Now substitute that back in:

\[ \text{Surface Area} = 2\pi(2)(7) \]

Calculate \( 2 \times 2 \times 7 \):

\[ 2 \times 2 = 4, \] \[ 4 \times 7 = 28. \]

So, the surface area is:

\[ \text{Surface Area} = 28\pi \text{ square inches}. \]

Thus, the answer is:

D. \( 28\pi \) inches\(^2\).