A box slides with an initial speed of 4.0 ms4.0\,\dfrac{\text m}{\text s}4.0sm4, point, 0, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction towards a spring on a frictionless horizontal surface. When the box hits a spring with spring constant k=150 Nmk=150\,\dfrac{\text N}{\text m}k=150mNk, equals, 150, start fraction, start text, N, end text, divided by, start text, m, end text, end fraction, the spring compresses by 0.30 m0.30\,\text m0.30m0, point, 30, start text, m, end text.