1) first of all *same amount* of work is done either to stretch or compress the same spring a given amount as long as the deformation is in the "elastic range" of the spring. Obvously the force direction is opposite between a stretch and compression.
SPE = 1/2kx� {where k = 4.2e4, x = 0.052}
SPE = (0.5)(4.2e4)(5.2e-2)^2= 56.784 = 56.784 J ANS ANS