An astronaut, whose mission is to go where no one has gone before, lands on a spherical planet in a distant galaxy. As she stands on the surface of the planet, she releases a small rock from rest and finds that it takes the rock 0.540 s to fall 1.90 m. If the radius of the planet is 8.60×107 m, what is the mass of the planet?

Will you chech and finish these for me, because i am stumped with them.

What should the power status of a circuit be when measuring resistance with an ohmmeter?

How does a circuit breaker protect a refrigerator? a. when the current is too high, a metal strip in the fuse melts and opens the circuit. b. when the resistance is too high , a re-settable which opens a circuit c. when the current is too high , a re-settable switch opens the circuit d. when the resistance is too high a metal strip in the fuse melts and opens the circuit