
Here's a complex question that requires someone to reason about the input, can you answer it?
Derby Racer was the name of how many wooden roller coasters that operated at Revere Beach in Revere, Massachusetts, both coasters were racing roller coasters, with side-by-side track pairs where two coaster trains would race each other around the circuit of the coaster, a roller coaster train is a vehicle made up of two or more cars connected by specialized joints which transports passengers around a roller coaster's circuit?


two
