ETHANSANCHEZ52GO ETHANSANCHEZ52GO Physics Answered what is the mass of a rock on the edge of a 40m cliff with 980 joules of potential energy? calculate a hammer's PEi with a KEi of 0J, a PEf of 10j, and a KEf of 185 J. if a 2kg bowling balls PEi is 100j and KEi is 21J, what is its final potential energy if it strikes the pins traveling at 6m/s? please show work with units