I really don't understand my physics class... Can anyone help me on these questions? 1. A ball falls from rest from a height of 490m. a. How long does is remain in the air? b. If the ball has a horizontal veolcity of 200m/s when it begins to fall, what horizontal displacement will it have? 2. A bridge is 176.4m above a river. If a lead weighted fishing line is thrown from the bridge with a horizontal velocity of 22.0m/s, how far has it moved horizontally when it hits the water?