6. Two forces of 50 N and 30 N, respectively, are acting on an object. Find the net force (in N) on the object if … a. the forces are acting in the same direction b. the forces are acting in opposite directions.

So, if the forces are in the same direction, it'll be 50N+30N= 80N!

If the forces are in opprsite direction it'll be 50N-30N= 20N (or visa-versa)

Explanation: This is because if the forces are in the same direction, like 2 people are pushing a body with 0 mass (I know, weird but imagine it) and both the people are applying the force in the same direction, let's say East, so the total fore exerted on the body will add up to become 50N+30N=80N.

And if the forces are phusing the body in oposite direction, then, let's say the bigger guy is pushing on the West Direction with 50N  of force and the weaker guy is pushing on the opposite direction with 30N of force, so this time their forces cancel out and it becomes 50N-30N= 20N (or 30N-50N= -20N).

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.