Help timed test!!:

What are the domain and range of f(x)=[1/5]x

Marcus and cody both leave the park at the same time, but in opposite directions. if cody travels 6 mph faster than marcus and after 4 hours they are 64 miles apart, how fast is each traveling? solve using rare times time = distance.

Which of the following is an example of a rational number? a. π b. √ 9 c. √ 8 d. 3.8362319