Science Homework Help

I need help with a Chemistry question. All explanations and answers will be used to help me learn.

1. A 3.00mL
sample of 5.00M NaOH is made to react with 20.0 mL HCl with a concentration of
0.500M. What is the pH of the final solution?

2. A 1.50M acetic acid solution reacts with 20.0 mL 0.200M NaOH. If 20.0 mL of acid is used, calculate the pH of the resulting solution. (K_a of acetic acid = 1.8×10^-5).