Weary Travelers Arrive at Will Rogers International Airport, Pick Up

Weary travelers arrive at Will Rogers International Airport, pick up their luggage, stumble to their cars, and proceed to the parking lot attendant to pay for their parking. Traveler interarrival times are exponentially distributed, as are the service times of the attendant. On average, travelers arrive every 25 seconds. The attendant can process three travelers per minute.
-Use the information in Scenario C.2.What is the probability that a traveler will pull up to the attendant's service window without having to wait for another customer?

A) Less than or equal to 0.15
B) Greater than 0.15 but less than or equal to 0.25
C) Greater than 0.25 but less than or equal to 0.35
D) Greater than 0.35