Question 15In the diagram, $ABCD$ is a square with $AB=20$ cm, $AD$ is a diameter of the semicircle, and $AB$ is a radius of the quadrant. Find the area, in cm², of the shaded region. $75\pi$ cm²$50\pi$ cm²$(75\pi-100)$ cm²$(50\pi-100)$ cm²None of the above
