PLEASE help it's timed!! :)

Which of the following graphs represents the function f(x) = 2^x

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

When you answer this can you explain