The object's velocity at time t is given by the function
v(t) = 19.6 m/s - (9.81 m/s²) t
and at its highest point the object has zero velocity. Solve for t in this instance:
19.6 m/s - (9.81 m/s²) t = 0
t = (19.6 m/s) / (9.81 m/s²)
t ≈ 2.00 s
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