A supply company manufactures copy machines. The unit cost of C (the cost in dollars to make each copy machine) depends on the number of machines made. If x machines are made, then the unit cost is given by the function C(x)=0.4x^2-232x+38,207. How many machines must be made to minimize the unit cost? Do not round your answer.

Which of the following transformations will result in an image that maps onto itself? a. rotate 90 degrees counterclockwise and then reflect across the y axis b. reflect across the x-axis and then reflect across the y-axis c. rotate 90 degrees counterclockwise and then translate 4 units up d. reflect across the x-axis and then reflect again across the x-axis