Which undefined term is needed to define an

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?

For f(x) = 3x+1 and g(x) = x2 - 6, find (g/f)(x)

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.