Step-by-step explanation:
You are given mass and delta-x (in meters)
then : mass * g = N
then calculate the spring constant k
here is the first line :
mass = .05 kg = .05 * 9.81= .4905 N
delta x = .012 m
spring constant = k = .4905 N / .012 m = 40.9 N/m
continue on with the other lines to calculate , k