Answer: 50.24 square centimeters.
Explanation:
Given: The radius of the circular lens of a magnifying glass = 4 centimeters
The area of a circle is given by :-
, where r is the radius of the circle.
Then the area of the circular lens of a magnifying glass is given by :-

Hence, the area of the circular lens of a magnifying glass = 50.24 square centimeters.