Mark slams on the brakes after traveling 25 m/s. It takes him 3 seconds to come to a complete stop. What is his acceleration?

Pls pls pls pls ! describe, in your own words, how you found the epicenter of the earthquake.

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

Which of these has some mechanical energy? a. an atom b. heat inside earth c. a book on a shelf d. the fire from a lit match