Answer is Mr and S as MgS ..
<u>Answer:</u> The force that must be applied is 15 N.
<u>Explanation:</u>
Force exerted on the object is defined as the product of mass of the object and the acceleration of the object.
Mathematically,

where,
F = force exerted = ?
m = mass of the object = 3 kg
a = acceleration of the object = 
Putting values in above equation, we get:

Hence, the force that must be applied is 15 N.
Comment above 100 percent correct
Answer:
longitudinal wave
Explanation:
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