Hydroxylapatite, Ca_10(PO_4)_6(OH)_2, has a solubility constant of K_sp = 234 times 10^-59, and dissociates according to Ca_10(PO_4)_ 6(OH)_2(s) rightwardsharpoonoverleftwardsharpoon 10Ca^2+(aq) + 6PO^3-_4(aq) + 2OH^-(aq) Solid hydroxylapatite is dissolved in water to form a saturated solution. What is the concentration of Ca^2+ in this solution if [OH^-] is somehow fixed at 1.90 times 10^-6 M? [Ca^2+] =