If a rock is thrown upward on the planet Mercury with a velocity of its height after seconds is given by the equation
1. Find the velocity of the rock after one second.
Velocity (in m/s):

2. Find the velocity of the rock when
Velocity (in m/s):

3. When will the rock hit the surface?
Time (in sec):

4. With what velocity will the rock hit the surface?
Velocity (in m/s):