4. a 62.0-kg person, standing on the diving board, dives straight down into the water. just before striking the water, her speed is 5.50 m/s. at a time of 1.65 s after she enters the water, her speed is reduced to 1.10 m/s. what is the net average force (magnitude and direction) that acts on her when she is in the water?

To solve this problem it is necessary to apply the concepts related to the Moment. The moment in terms of the Force and the time can be expressed as

F = Force

At the same time the moment can be expressed in terms of mass and velocity, mathematically it can be given as

Where

m = Mass

Change in velocity

Our values are given as

By equating the two equations we can find the Force,

Therefore, the net average force will be:

The negative symbol indicates that the direction of the force is upwards.

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.