A tennis ball is thrown vertically upward with an initial velocity of +3.0 m/s. a. What will the ball's speed be when it returns to its stating point? b. How long will the ball take to reach its starting point? c. Find the maximum height reached by the ball.

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

Two objects of different mass start from rest, are pulled by the same magnitude net force, and are moved through the same distance. the work done on object 1 is 900 j. after the force has pulled each object, object 1 moves twice as fast as object 2. how much work is done on object 2?

What component of earth’s atmosphere exists entirely as a result of photosynthesis?