A person runs off a cliff into a lake below. If the person leaves the cliff without a horizontal velocity of 4m/s, how far way from the cliff does he land is the cliff is 17m high?

When you drop an object from a height of 17m, it hits the ground 1.86 seconds later, with a speed of  18.25 m/s.That's the same time it takes our daredevil to hit the water.  During the 1.86 seconds that he's falling and yelling, he's traveling 4m/s horizontally, and lands 7.45 meters from the bottom of the cliff.  Let's hope the water begins closer to the cliff than that.