#### Answer

The period of a mass-spring system is:-
$T=2\times pi \times \sqrt \frac{m}{k}$
m is mass and k is the spring constant.
It is independent of the gravitational acceleration. So if a mass spring system is taken to moon, its period remains unchanged.
The period is given by $T=2\times pi \times \sqrt \frac{l}{g}$
l being the length of the pendulum and g is the gravitational acceleration.
Since the period is inversely proportional to g, its period increases when it is taken to moon as g is less on the moon as compared to on the earth.