Answer: The central angle measure is 126°
Explanation:
The circle has a radius of 20cm
The area of a sector of a circle of an angle A is:
Area = (A/360°)*pi*r^2
where r is the radius.
Here we have that the area is (140*pi) cm^2
let's find the value of A.
(140*pi) cm^2 = (A/360)*pi*(20cm)^2 = (A/360)*pi*400cm^2
140 cm^2 = (A/360)*400 cm^2
A = (140/400)*360° = 126°
The central angle measure is 126°