If the Tris buffer was exactly at pH=9, then calculate the pH values for tube 4 (undiluted), tube 5 (1/2 dilution), and tube 6 (1/10 dilution) after...

If the Tris buffer was exactly at pH=9, then calculate the pH values for tube 4 (undiluted), tube 5 (1/2 dilution), and tube 6 (1/10 dilution) after the addition of 1 ml of 0.05 M HCl.

Test tube 4: 4 ml of 0.1 M Tris pH 9, + 1 ml 0.05 M HCl

Test tube 5: 4 ml of 0.050 M Tris pH 9, + 1 ml 0.05 M HCl

Test tube 6: 4 ml of 0.010 Tris pH 9, + 1 ml 0.05 M HCl

Please show work!