2 is not r=k[A]n[b]m because r is reaction rate, not reaction time.
For number 1), what's the relationship between speed and the time needed to travel 1 km? If speed increases by a factor of 2, what happens to time? Speed is analogous to reaction rate and time of travel is analogous to reaction time.
Hint: number 3 will be simple after you get number 1
