The average rate of change for the interval of x from 0 to 5 can be calculated by the following formula of the average rate of change:

Using the formula for each of the functions, we have:
f(x): (0, 0) and (5, -20)
g(x): (0, 17) and (5, 2)
h(x): (0, 13) and (5, 8)
the rates are:
The order of the functions, from the smaller to the bigger, is:
f(x) , g(x) , h(x)