J. J. Thomson theorized that, if an atom had all of its negatively charged electrons removed, the remaining material would be
A. neutral
B. negatively charged
C. positively charged
D. magnetic

B. hope it helps :)

Explanation:

d) the number of neutrons plus the number of protons

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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