4) You are given the following: 0.5 M KH2PO4, 0.5 M K2HPO4, solid Tris base, solid Tris-HCl, and 3 M NaCl. Calculate how you would prepare of each of the following: a. 50 ml of 10 mM Tris-Cl pH 8.0 b. 50 ml of 10 mM K+ Phosphate buffer, pH 7.2 c. 50 ml of 0.010 M NaCl