A Zip-liner is gliding along a horizontal wire over a lake. They must release themselves from the wire and drop down to the water to get off the zip-line. They are 4.80 m above the water and release themselves when they are travelling at 4.00 m/s. How fast are they travelling when they hit the water? 13.7 m/s 5.70 m/s 10.5 m/s 4.00 m/s