1. The problem statement, all variables and given/known data A ball is thrown vertically upward at 96 ft/s from the roof edge of an 80 ft tall building. What is the ball's total time in air (from when thrown). 2. Relevant equations 3. The attempt at a solution I calculated that the ball reaches a height of 0 ft in 6 s. Then to fall -80 ft, I used -80=0+(-96)t-16t^2. I got -96 ft/s as vo in this part of the problem because i assumed the velocity when ball comes back down at the roof's edge is equal and opposite to ball's initial velocity of 96 ft/s. The answer says 6.74 s. But i got 6.74 s to fall that 80 ft. And then I added 6.74 to 6 s to get time in air.