For each long-distance call anywhere in the continental United States, a new phone service will charge users $0.30 per minute for the first 2 minutes and $0.02 per minute for additional minutes in each call. Tom’s current phone service charges $0.10 per minute for all calls, and his calls are never shorter than 7 minutes. If Tom’s dorm switches to the new phone service, what will happen to the average length of his calls?