Two men are carrying a uniform ladder 6 m long with a mass of 40 kg. if one of the men lifts with 150 N at one end of the ladder, a) where (in terms of distance to the end where the first man lifts), and b) how much force must the second man lift?

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.