A person crosses a 600 m long street in 2 minutes. What is his speed in km per hour? Select:  A) 12  B) 24  C) 18  D) 42  E) 64

Rationale: distance = 600 meter time = 2 minutes = 2 x 60 seconds = 120 seconds speed = distance / time = 600 / 120 = 5 m / s = 5 ã — 18 / 5 km / hr = 18 km / hr answer : c
Answer: C