I only need b and d but im confused​

Look at the following graph of the given equation. determine whether the equation is a function. explain why or why not.

Find the difference (8ab+a+2) - (3ab+6)

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?