ok so here's one: A helicopter is ascending vertically with a speed of 5.50 m/s. At a height of 155 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? [Hint: The package's initial speed equals the helicopter's.] and here's the other: A rock is dropped from a sea cliff and the sound of it striking the ocean is heard 4.8 s later. If the speed of sound is 340 m/s, how high is the cliff? (no idea how to even begin that one...) Um, i know that in both of them we're supposed to use the quad. formula and in the first one I tried to but webassign told me I was wrong. I got 11.1s i think. The second I don't even know how to start. If anyone can do them, can you please explain how you got it? I wanna know how to do them so I don't make mistakes later on in the year. Thanks.