The height, h, in feet of a golf ball above the ground after being hit into the air is given by the equation, h = -16t^2 + 64t, where t is the number of seconds elapsed since the ball was hit. how many seconds does it take for the golf ball to hit the ground?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.