A car starts with constant acceleration $ a=2 m/s^2$ at $t=0$ Two coins are released from the car at $t=3$ and $t=4$. Each coin takes 1 second to reach the ground.Then distance between two coins is (assume the coin stick to ground)

Question

\[(a)\;9 m \quad (b)\;7 m \quad (c)\;15 m \quad (d)\;2 m\]