A 5.0 kg mass hanging from a spring scale is slowly lowered onto a vertical spring, as

Question:

A 5.0 kg mass hanging from a spring scale is slowly lowered onto a vertical spring, as shown in FIGURE EX9.29. The scale reads in newtons.
a. What does the spring scale read just before the mass touches the lower spring?
b. The scale reads 20 N when the lower spring has been compressed by 2.0 cm.
What is the value of the spring constant for the lower spring?
c. At what compression will the scale read zero?

Scale FIGURE EX9.29 HWww