Greg takes 15 minutes longer than Mindy does to make the 112-mile drive between two cities. Mindy drives 8 miles an hour faster. How fast do Greg and Mindy drive?
(a) Greg: 48 mph, Mindy: 56 mph
(b) Greg: 52 mph, Mindy: 60 mph
(c) Greg: 56 mph, Mindy: 64 mph
(d) Greg: 60 mph, Mindy: 68 mph