I suck at math and this is super hard

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. how many hours after the truck's departure will the two meet?

What are the domain and range of the function f(x)=2^x+1

Find an bif a = {3, 6, 9, 12) and b = {2, 4, 6, 8, 10).