A Spring in Equilibrium Is 0

Multiple Choice

A spring in equilibrium is 0.8 meters long and an external force of 2 Newtons stretches the spring to a length of 1.2 meters. The work done by the spring force in stretching it from equilibrium to 3 meters, in Newton-meters, is
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A) -15.3
B) -13.7
C) -12.1
D) -11.8
E) -10.7