8 A 0.5 kg block attached to a spring is pulled a distance of 20 cm horizontally and released. If the period of the oscillation is 0.8 s, what is the kinetic energy of the block at t=0.2 s?
(A)0.42J
(B)0.62J
(C)0.82J
(D)1.02J
(E)1.24J

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