Answer:
3.92 cm
Step-by-step explanation:
Assuming spring cinstant of 800 N/m, we know that the potential energy is transformed to kinetic energy in spring hence
where m is the mass of the block, g is acceleration due to gravity, x is the extent of compression of the spring and k is spring constant. Making x the subject of the above formula then

Substituting 1.6 kg for m, 9.81 for g and 800 N/m for k then
