Phobos orbits mars with a period of 0.32 days and is a mean distance of 9.4 x 10^3km from mars. deimos also orbits mars with a mean distance of 2.35 x 10^4 km please answer A and B

Ben(55 kg) is standing on very slippery ice when junior(25kg) bumps into him. junior was moving at a speed of 8m/s before the collision and ben and junior embrace after the collision. find the speed of ben and junior as they move across the ice after the collision .

An object weigh 40n in air ,weigh 20n when submerged in water,and 30n when submerged in a liquid of unknown liquid density.what is the density of unknown of liquid?

What is the measurement of how fast an object moves relative to a reference point?