A weightlifter lifts a set of weights a vertical distance of 2.0 m. If a constant net force of 350 N is exerted on the weights, what is the net work done on the weights?

700 Joules

Explanation:

The work done equals force times distance. Just multiply your two values there.

Side note: It would be more impressive if he'd done it in 1 second rather than 5. You know why? Because POWER=WORK/TIME. The less time it takes him to lift the weight with the same force and distance, the more powerful he is!

fgravity=10x10=100n case 1

fgravity=30x20=600n case 2

6 times more

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.