Answer:
C. Planet D has the greatest mass and will exert a greater gravitational force
Downwards - from uphill towards the lowlands and eventually into the sea.
Explanation:
Displacement is the straight line distance from the starting position to the final position.
Person X walks halfway around circle. So her displacement is 100 m.
Person Y walks 3/4 of the way around. So his displacement is 50√2 m ≈ 70.7 m.
Person Z walks completely around the circle, so their displacement is 0 m.
Therefore:
Z < Y < X
when a hole is made at the bottom of the container then water will flow out of it
The speed of ejected water can be calculated by help of Bernuolli's equation and Equation of continuity.
By Bernoulli's equation we can write

Now by equation of continuity


from above equation we can say that speed at the top layer is almost negligible.

now again by equation of continuity


here we have


now speed is given by


The correct answer is D: which is none of the above.
Hint: a wreckling ball contains pontential energy that acts like a pendulum
a pot of water contains pontential thermal energy