At maximum height, $v = 0$
At $t = 2$ s, $a = 6(2) - 2 = 12 - 2 = 10$ m/s$^2$ practice problems in physics abhay kumar pdf
$\Rightarrow h = \frac{400}{2 \times 9.8} = 20.41$ m At maximum height, $v = 0$ At $t
Given $v = 3t^2 - 2t + 1$