**Answer:**

well, in my view,

In fluid mechanics, hydrostatic equilibrium or hydrostatic balance (also known as hydrostasy) is the condition of a fluid or plastic solid at rest. This occurs when external forces such as gravity are balanced by a pressure-gradient force.

**Answer:**

Acceleration,

**Explanation:**

We have,

Mass of the object is 20 kg

Force acting on the object is 100 N

It is required to find the resulting acceleration of the object. Let a is the acceleration. The force acting on object is given by :

a is acceleration

So, the resulting acceleration of the object is .

Answer:

b. Medicine balls

Explanation:

A medicine ball (also called an exercise ball, or a health ball) is a weighted ball about the shoulder diameter (approx. 13.7 inches), often used for recovery and strength training.... In 1705 similar large balls had been used in Persia.So you can use your medicine ball as a projectile to boost the strength of your throws.

**Answer:**

1.67 m/s

**Explanation:**

Since this is an inelastic collision (the block and the arrow stick together after the collision), we can solve the problem by using the law of conservation of momentum:

where

is the mass of the arrow

is the initial speed of the arrow

is the mass of the block

is the initial speed of the block

is the final speed of the arrow+block

Substituting and re-arranging the equation, we find:

**Answer:**

Joule (J)

**Explanation:**

Joule (J) is the SI unit of heat energy (any energy - thermal, electrical, mechanical..). It is named after the English physicist James Prescott Joule.