A vertical mass-spring oscillator is displaced 2.0 \mathrm{~cm} from equilibrium. The 100 \mathrm{~g} mass passes through the equilibrium point with a speed of 0.75 \mathrm{~m} / \mathrm{s}. What is the spring constant of the spring?
Answer Choices
A. 90 \mathrm{~N} / \mathrm{m}
B. 100 \mathrm{~N} / \mathrm{m}
C. 110 \mathrm{~N} / \mathrm{m}
D. 140 \mathrm{~N} / \mathrm{m}
E. 160 \mathrm{~N} / \mathrm{m}