Option A: Salary A = 14000 + 0.1*s; Option B: Salary B = 20000 + 0.04*s, where s is your sales amount. Equilibrium: A = B, or 14000 + 0.1*s = 20000 + 0.04*s, 0.1*s - 0.04*s = 20000 - 14000, 0.06*s = 6000 ====> s == = 100000. Answer. Option A produces a larger paycheck after $100000 sales.