Adragster going at 5 m/s north increases its velocity to 23 m/s north in 4 seconds. what is its acceleration during this time interval?

To my recollection vf=vi+at
23m/s=5m/s + a (4s)
get the like units together
23m/s - 5m/s = a (4s)
18m/s = a (4s)
divide each side by 4 to find a
18m/s / 4s = 4.5m/s

I don't know how to do the up arrow to square any of the m/s.

It won't lose or gain electrons if it's a covalent bond it shares the electrons with another atom or atoms. if it is an ionic bond it will lose the 3 electrons on the outer shell and become a positively charged ion.  credit goes to @sunshinebaby of answers.yahoo.com.

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