The diameter of the plate of parallel platecapacitor is 6cm.if its capacity is equal to that of sphere of diameter 200cm,seperation between plate of condensor is

The question says that the capacity of the parallel plate capacitor which is
C = ?oA/d is equal to the capacitance of the sphere of radius R and the self capacitance of the conducting sphere of radius R is given as
C = 4 * pi * ?o R
So, both the equations are equated to get the final answer.