Final answer:
To find the area of the circular base with a 4 ft radius, you use the formula A = πr², which gives approximately 50 ft². This matches option 3) 50.24 sq. ft.
Step-by-step explanation:
The question asks us to calculate the area of a circular base with a given radius of 4 ft. The formula to find the area of a circle is A = πr², where A is the area, and r is the radius of the circle. To solve for the area with the radius of 4 ft, we plug in the numbers into the formula:
A = π(4 ft)²
A = π(16 ft²)
A = 3.1415927... × 16 ft²
A = 50.2654825... ft²
Because the radius was given with only one significant figure (4 ft), the result should be rounded to one significant figure as well. Therefore, the area of the circular base is approximately 50 ft², which corresponds to option 3) 50.24 sq. ft. if we do not consider significant figures.