The surface area \( A \) of a cone (the nón lá) can be calculated using the formula:
\[ A = \pi r l \]
where:
- \( r \) is the radius of the base of the cone,
- \( l \) is the slant height of the cone.
First, we need to find the radius \( r \) from the diameter: \[ r = \frac{\text{diameter}}{2} = \frac{38 , \text{cm}}{2} = 19 , \text{cm} \]
Now, we can plug in the values into the surface area formula. Using \( \pi = 3.14 \) and \( l = 30 , \text{cm} \):
\[ A = 3.14 \times 19 , \text{cm} \times 30 , \text{cm} \]
Calculating the components one step at a time:
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Calculate \( 19 \times 30 \): \[ 19 \times 30 = 570 \]
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Now multiply by \( \pi \): \[ A = 3.14 \times 570 \] \[ A = 1,791.8 , \text{square centimeters} \]
So the surface area of the nón lá is approximately 1,789.8 square centimeters.
Thus, the correct response is:
1,789.8 square centimeters.