HELP "An astronaut on an alien planet drops a rock into a crater which is 100 meters deep. The rock hits the bottom of the crater 4 seconds later. Is the gravity on this planet stronger or weaker than that of Earth?"

explanation:

could i give you a exaplo that could you?

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods

there are no contact forces mentioned on the list of choices that you've provided.