Question

This semicircle has a diameter of 5 meters.

Answer 1

Area of semicircle is given by:
$A_sc = \frac{1}{2} \pi r^2$

r is the radius, and we are given the diameter. Radius is half the diameter, so it's 2.5m. Let's plug that into the formula (using 3.14 as an estimation for pi):
$A_t = \frac{1}{2}(3.14)(2.5)^2 = 9.81m^2$

So, the area of this semicircle is 9.81m².