Answer:
a) 142.98 cm b) 53.98 cm c) 1.46 kg d) 1.46 kg
Step-by-step explanation:
Using the equation for the period of a simple pendulum we can answer the first 2 questions.
a)

b)

Using the equation for the period of a mass-spring system we can answer the last 2 questions.
c)

d)

we can observe that the period of this system does not depend on the value of gravity.