I owe 600 shares common stock , I currently received cash dividend of .42 per share a year. A 5% stock dividend, was declared, how many shares of coomon stock would I receive as a dividend?

First of all it starts with "I owe" was confusing. Owe and Own has opposite meanings. It won't make any sense later you mentioned that you are receiving dividend.

Let's assume you meant you have 600 shares. You will receive the shares you have multiply the percentage they are going to issue as your stock dividend.