The two-second rule.
It is a common guideline to follow while driving.
It means that any given driver should be AT LEAST two seconds behind any vehicle that is driving in front of his vehicle. It might apply for any kind of vehicle.
Answer:
a)
, b) 
Explanation:
a) The potential energy is:



b) Maximum final speed:

The final speed is:


Answer:
Maybe because you not throwing it stringer or lighter. And you need to control yourself prob. maybe you did line it correctly or maybe your just bad to be honest. -.-
Explanation: