Please explain why thanks

Mary uses funds from a savings account to pay off his equipment loan. The interest rate Mary pays on the equipment loan is smaller than the interest rate he can earn on the savings account (3%). John's accounting profit and his economic profit Tip: Accounting Profits = Economic Profits - opportunity costs. Rises, falls Stays the same, rises Stays the same, stays the same Rises, rises Since some inputs you need to study are generally fixed your productivity as a student will tend to: increase increase at a decreasing rate O decrease at an increasing rate decrease