a). Water is still H₂O after it freezes.
b). Ice is still H₂O after it melts.
c). Wire is still Cu when it's bent.
d). Paper combines with the O₂ in the air, and turns into
a lot of new compounds when it burns.
A. microscopes !!!!!!!!!!
Answer:
a) 



b) 
Explanation:
From the exercise we got the ball's equation of position:

a) To find the average velocity at the given time we need to use the following formula:

Being said that, we need to find the ball's position at t=2, t=2.5, t=2.1, t=2.01, t=2.001



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b) To find the instantaneous velocity we need to derivate the equation


<span>action is the one car hitting the other, reaction is the other car being pushed away</span>