Answer:
Step-by-step explanation:
Comment
I'm going to assume that this is not a closed figure. The top is open like a water trough for horses.
There are 2 semicircular ends which add up to 1 whole circle.
There is 1 base area. The base area has a width of one of the semicircles. It has a length of 15 cm.
Solution
2 semi circles
r = d / 2
r = 20/2
r = 10
Area = pi r^2 This area is for 2 semicircles which = 1 circle.
Area = 3.14 * 10^2
Area = 3.14 * 100
Area = 314
Trough
r = d / 2
d= 20
r = 20/2
r= 10
w = 2*pi*r / 2
w = 2*3.14 *10/2
w = 31.4 cm
L = 15 cm
Area = 15 * 31.4
Area = 471
Total Area = 785
