F = m*a
5000 = 2000 * x
5000/2000 = x
2.5 = x
2.5m/s^2 = a
D.) In order to calculate both of them, we must know the "FORCE" on the system.
C because the the smallest thing then the other ones because it never said what kind of size of it
By tightening a string you are actually putting more stress on the string you are giving it a new frequency that isn't natural.
Hope this helps
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