The Earth and the Moon circle their common center of mass, and
that common center of mass is what circles the Sun, once a year.
Rarefactions are where you see the wave further apart. Where it's closer together, it's called a compression.
Answer:

Explanation:
Acceleration, 
Where v and u are the final and initial velocities of the race car respectively, t is the time taken for the race car to attain velocity of 36 m/s.
Substituting 36 m/s for v, 28 m/s for u and 2 s for t then

Answer:
300W
Explanation:
from my years in middle school, i have learned the equation is energy =power*time is 300W
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