In the diagram, K, O and M are the centers of the three semi-circles. OC = 32 and CB = 36,
What is the area of the semi-circle with center k?
Ok let's do this
the diameter of circle M is  so the radius is 18, the area of semicircle M is 18^2*pi which is 324pi then /2 which is 162pi
Now let's move on, the radius of circle O=32+36 which is 68, that will equal to (68^2)/2 which is 2312 and the diameter is 
Now with these two Diameters, we can find the area of circle K, first we find the radius, that will be (136-36)/2 which is 50, then 50^2/2 which is 1250, finally multiply by pi and we get