Help will give crown Find the missing side length

Which of the following graphs could represent a quartic function?

What is the value of x in the equation7x+2y=48 when y=3

Technicians have installed a center pivot, circular irrigator for a farm that covers 25 acres. a.) how long is the irrigation boom (in feet) from the center pivot to its farthest extent? b.) if the irrigation boom makes 4 full revolutions in a day, how many miles does the end of the boom travel in 5 days?