Teacher:Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.
Teacher: Now, understand the problem? Solve this instance: Problem: the length of the bridge, which a train 155 metres long and travelling at 45 km / hr can cross in 30 seconds, is ?
Options: a. 76 m, b. 178 m, c. 220 m, d. 187 m, e. 176 m
Student:
c