To find the surface area of a cylinder, you can use the formula:
\[ \text{Surface Area} = 2\pi r(h + r) \]
where:
- \( r \) is the radius,
- \( h \) is the height,
- \( \pi \) is approximately \( 3.14 \).
Given:
- \( r = 4 \) cm
- \( h = 9 \) cm
Now, plug the values into the formula:
\[ \text{Surface Area} = 2 \times 3.14 \times 4 \times (9 + 4) \]
Calculating the height plus radius:
\[ 9 + 4 = 13 \]
Now replace back into the formula:
\[ \text{Surface Area} = 2 \times 3.14 \times 4 \times 13 \]
Calculating step-by-step:
-
Calculate \( 2 \times 3.14 \): \[ 2 \times 3.14 = 6.28 \]
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Now, calculate \( 6.28 \times 4 \): \[ 6.28 \times 4 = 25.12 \]
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Finally, multiply by 13: \[ 25.12 \times 13 = 326.56 \]
Therefore, the surface area of the cylinder is:
\[ \text{Surface Area} = 326.56 , \text{cm}^2 \]
Thus, the correct answer is:
326.56 cm²