Erica sutherland earns a yearly salary go 45,650, how much would erica earn in a monthly paycheck

What is the y-intercept of the line given by the equation

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)

Wrote and expression for the difference of p and 4