A 0.5 kg ball is thrown vertically upward at a speed of 25 m/s. Its velocity, v(t) (in m/s), at time, t (in seconds), is given by v(t)= 25-9.8t

Its kinetic energy, K(v) (in Joules), is given by K(v)=0.5v^2.
Express the ball's kinetic energy as a function of time, K(t).

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