1. A particle moves along the y axis. Its position is given by the equation \( y(t) = 2 + 3t - 4t^2 \), with y in meters and t in seconds. What's its position when it changes direction?
(A)2.56 m
(B)1.28 m
(C)4.23 m
(D)2.12 m
(E)3.84 m
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統計: 尚無統計資料
統計: 尚無統計資料