Area of the shaded region would be 379. 688 ft²
To determine the area, we can see that the composite shape is made up of a cube and also a semi-circle.
The formula for area of a cube is expressed as;
Area = s²
such that 's' is the length of the side of the cube
Substitute the values, we have;
Area = 25²
Area = 625 ft²
Then, for the area of the semi -circle, we have;
Area = πr²/2
Area = 3.14 × 12.5²/2
Multiply the values
Area = 490. 63/2
Area = 245. 313 ft²
Area of the shaded region would be;
= Area of cube - area of semi -circle
= 379. 688 ft²