Based on the information below for Benson Corporation, what is the optimal capital structure? Debt = 50%; Equity = 50%; EPS = $3.05; Stock price = $28.90 Debt = 60%; Equity = 40%; EPS = $3.18; Stock price = $31.20 Debt = 80%; Equity = 20%; EPS = $3.42; Stock price = $30.40 Debt = 70%; Equity = 30%; EPS = $3.31; Stock price = $30.00 Debt = 40%; Equity = 60%; EPS = $2.95; Stock price = $26.50