Can any kind soul help me please

Identify an equation in point slope form for the line perpendicular to y=3x+5 that passes through (4,-1)

Olga used 100 ounces of flour to make 225 muffins. how many ounces of flour will be used to make 300 muffins?

After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2. after how many seconds will the ball hit the ground before rebounding?