See explanation
Explanation:
Hookes law states that; the displacement due to a stretching force is directly proportional to the magnitude of the deforming force.
F = ke
F = deforming force
k = force constant
e = extention
k = F/e
k = 4N/0.06 m= 66.67 Nm^-1
To determine the extension of the spring produced by the 4.0 N weight
1) We measure the original length of the spring
2) We measure the length after hanging the 4 N mass
3) Subtract the new length from the original length to determine the extention.