I need help understanding. Can someone please help by breaking down the steps to solve I am just not understanding thank you! The phosphate anion is

I need help understanding. Can someone please help by breaking down the steps to solve I am just not understanding thank you!

The phosphate anion is a common industrial pollutant whose presence in fresh water promotes the growth of algae and general degradation of water quality. Investigate the solubility tables and suggest salts that could be reacted with the phosphate anion, PO_4^(3-), which would result in its precipitation out of the water?

What is a spontaneous process and do spontaneous processes occur under all conditions? Does water spontaneously boil at 760 mm Hg pressure and at a temperature of 100 °C. Explain why or why not? What, if any, relationship exists between the spontaneity of a process and the rate at which the process occurs.