answer 2 & 3 please

1. Calculate the concentration that OH must exceed in a 0.010M solution of Fe(NO3), in order to precipitate Fe(OH)3 2. Using the Fe(OH)3 solution in problem 1, calculate the solubility of Fe(OH), in grams per liter in a solution buffered at a pH of 3.0. Explain using solubility calculation why Fe(OH), will be more or less soluble at a pH of 9.0. 3. (Think question). At what pH should the solution be buffered to only precipitate out Fe(OH), when your sample solution contains Fe*3 and Cu*2 ions. If this is not possible, then explain why using solubility rules