7. Which best describes the energy change th pushes a large rock down a hill? A: sound energy kinetic energy
B:, potential energy kinetic energy
C: kinetic energy mechanical energy
D: mechanical energy sound energy​

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton