Matter, substance. Material howya call it.
To solve the problem it is necessary to use the concepts related to the calculation of periods by means of a spring constant.
We know that by Hooke's law

Where,
k = Spring constant
x = Displacement
Re-arrange to find k,




Perioricity in an elastic body is defined by

Where,
m = Mass
k = Spring constant


Therefore the period of the oscillations is 0.685s
Hi my friend, since momentum is always conserved without external forces, the momentum after the collosion will still be 0.06 kg*m/s. Hope it helps☺
Answer:
65.2 %
Explanation:
Let Q1 = Heat absorbed by the system
Q2 = Heat released by the system
e= (1 - (Q2/Q1)) x 100
e= (1 - (750/2150)) x 100
e= (1 - 0.348) x 100
e= 0.652 x 100
e= 65.2 %