6 9 12 15 Question 1 (2 points) What principal will have a future value of $640, at 12.1% in 6 months?$600 $600 $678.72 $603.50 Question 2 (1 point) Which of the following represents the excess of the selling price per unit of a product over the variable cost of obtaining and selling each unit? Unit contribution margin Operating income Net income