The units of pressure are called derived units because it is derived from base unit, which is distance and a derived unit which is force. Force is derived from acceleration, a derived unit as well, and mass, a base unit; which makes it a derived unit.

**Answer:**

Kinematics is the study of how things move while dynamics is the study of forces and motion

**Answer:**

t=0.417s

**Explanation:**

After the ball hits the racket it is in freefall(assume air resistance as negligible)

so a=-g

use

x-x0=v0t+1/2at^2

Plug in givens

20=50t-4.9t^2

Solve quadratic equation using quadratic formula

t= 0.417 seconds, (the other answer is extraneous because it is too big because in 1 second, the ball travels 50 meters)

**Answer:**

Vectors have a size and a direction

vectors can have positive or negative values

**Explanation:**

**Answer:**

heathy, people, apple, motivational, together

**Explanation:**