A tension spring opposes being stretched, but offers no resistance to being compressed

Question

(think of a slinky!). A tension spring, with an equilibrium length of 1.25 m, is suspended
by one end from a ceiling at a height of 2.5 m above the ground; a mass of 100 g is
attached to the other end of the spring.
(a) If the mass is initially held and released from a height of 1.5 m above the ground
describe how the gravitational potential energy, kinetic energy and elastic potential
energy of the system change as the mass fall towards the ground. (3 points)
(b) What is the smallest spring constant that will prevent the mass from touching the
floor? (2 points)