1. **State the problem:** Robert Bryan, Jr. earns a base weekly salary of $400 plus 3% commission on sales exceeding $7,000. We need to find his total weekly earnings if he sells $21,000. 2. **Identify the formula:** Total earnings = Base salary + Commission on sales over $7,000. 3. **Calculate the sales exceeding $7,000:** $$\text{Excess sales} = 21000 - 7000 = 14000$$ 4. **Calculate the commission:** $$\text{Commission} = 0.03 \times 14000 = 420$$ 5. **Calculate total earnings:** $$\text{Total earnings} = 400 + 420 = 820$$ 6. **Conclusion:** Robert's weekly earnings are $820. **Final answer:** 2) $820