Step-by-step explanation:
General formula for the area of a circle = πr^2.
Since the diameter is 8, the radius is 4 (half of diameter)
So the area is π(4)^2 = 16π.
Its A (The area of Building C minus the area of Building B equals the area of Building A)
B 0.8 because the probability of rainy days 0.2 then the probability of sunny days is 0.8