Yesterday (April 22, 2015), Dr Jerico Wong, a prominent researcher and experimental physicist at SciCorp Industries in Chattanooga, Tennessee, had monumental successes in his cold fusion experiments. Although final testing has not yet been completed, and there has been no official press release, news this big travels fast, and a few hours later, a few teams of researchers at rival companies had learned of Wong's groundbreaking, world-changing finds.
The next day, as Wong was in the parking garage while leaving his workplace at 5pm, his face was covered and he was quickly forced into a van, which drove away. He heard the voice of a man saying, "Don't make a sound." As they started driving, Wong felt ear muffs being put on his head, on top of the covering that was already there, and he could not hear anything. For around 2 hours, he sat still in fear and silence, wondering if he would survive.
Then, as he slowly turned his head against the van wall, the ear muffs moved slightly, and he could hear the 2 men in the front seats talking, but he couldn't make out all of the words.
He heard:
Man #1: We (2-3 words garbled) warehouse in 5 minutes. You want (2-3 words garbled) pizza?
Man #2: Yeah, but there's a hundred of them in (1 or 2 words garbled). How about that one (1-2 words garbled)?
Man #1: What's that phone number on the window? I'll order delivery.
Man #2: (3 garbled numbers)-555-2 (3 garbled numbers) (garbled phone conversation)
Man #1: (3-4 garbled words) grub by 7:45*
EDIT: *After much thought, I changed the time above from 7:30 to 7:45
Wong knew that they had been traveling with almost no stops or turns; therefore, they must have been on one of the interstate highways. He also figured that they were in a fairly large city because one of the men said there were a hundred pizza places.
Wong knew that there were 4 possibilities of where he was:
Nashville, TN
Knoxville, TN
Birmingham, AL
Atlanta, GA
After some thought, he figured out where he was. Wong found it strange
that they didn't even think to check his pockets. He used the cell phone in his pocket to secretly text his friends: "Help. They've taken me to a warehouse in [city name]", which eventually led to him being rescued.
How did he know which of the 4 cities he was in?
EDIT: There are 2 realizations required to solve this. The simpler one has been figured out already, but the more "Eureka" one has not.