I’ve figured out all of these except for the third and fifth problems. please help !

Find the value of ax 4 ; a = 2, x = 1. select one: a. 2 b. 4 c. 1 d. 8

Which of the following contains a variable?

Miss henderson wants to build a fence around a rectangular garden in her backyard in the scale drawing the perimeter of the garden is 14 in of the actual length of a b is 20 ft how many feet of fencing what you need