On a velocity - time graph, if the line crosses the x - axis it depicts that the object has started moving in the opposite direction.
41.2 = h-1/2g(t-1)^2
<span> {-h = -1/2gt^2-1/2g+g*t-41.2
</span><span> {h = 1/2gt^2
</span><span> summing them up
</span><span> 0 = -1/2g+g*t-41.2
</span><span> 41.2 +4.9 = g*t
</span><span> t = 46.1/9.8 = 4.70 sec
</span><span> h = 1/2gt^2 =4.9*(4.70^2) = 108.241 m </span>
I believe the answer is b