please help and explain the answer!

Answer:
462 cm^2
Step-by-step explanation:
The centerline of the cloth area has a radius of (28 cm + 14 cm)/2 = 21 cm, so its length will be 1/4 of the circumference of a circle of that radius:
cloth centerline length = (1/4)·2πr = (π/2)·21 cm = (22/7)/2 · 21 cm = 33 cm
The width of the cloth portion is ...
28 cm - 14 cm = 14 cm
so the area of the cloth portion will be the product of centerline length and width:
(33 cm)(14 cm) = 462 cm^2