[填空题]
The graphs of displacementh)0k9ab jx3 mu, velocity and acwgd3tvi,j9n9yc zq/ j b()* zuceleration of a roller coaster in a theme park a( i9n*bj3/tdqyj ,uv9cw zz)gre shown in the following diagram.
1. Complete the following table by noting which graph A, B or C corresponds to each function.
When function is displacesment ;the graph is
When function is acceleration ;the graph is .
2. Write down the value of t when the velocity is greatest.
t= .