This one is for 15 pts. the next question is for 20

a = 0.75 m/s²

Explanation:

I am not gonna rewrite the stuff from previous answers, it's the same format.

a = average acceleration  

v = final velocity = 9 m/s  

v0 = initial velocity = 3 m/s

t = time = 8 s

a = (v-v0)/t

a = (9m/s - 3m/s) / 8s

a = 0.75 m/s²

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )

this is poiselle's equation from fluid mechanic in physics. mech eng