Question 15 (Mulbple Choice Worth 1 points)
(Types of Area MC)
A home gardener is building a greenhouse in the shape of a hemisphere. The radius of the hemisphere is 12.3 meters, and construction costs are $\$ 25$ per 100 square meters. What $i$ total cost of construction?
$\$ 59.41$
$\$ 237.65$
$\$ 475.39$
$\$ 950.58$

Step 1 ：Given that the radius of the hemisphere is 12.3 meters and the construction cost is $25 per 100 square meters.

Step 2 ：The surface area of a hemisphere is given by the formula \(2\pi r^2\), where \(r\) is the radius of the hemisphere.

Step 3 ：Substitute \(r = 12.3\) into the formula to get the surface area of the hemisphere.

Step 4 ：The surface area of the hemisphere is approximately 950.58 square meters.

Step 5 ：The cost of construction is calculated by multiplying the surface area by the cost per 100 square meters.

Step 6 ：The total cost of construction is approximately $237.65.

Step 7 ：\(\boxed{\$ 237.65}\) is the total cost of construction.