The solubility product of lead chromate is 2.0x10^-16 calculate the solubility in moles per liter of lead chromate in each of the following solutions:
a) saturated lead chromate in water
b) saturated lead chromate in 0.10 M Na2CrO4 solution
c) saturated lead chromate in 0.001 M Pb(NO3)2 solution