Two cars are moving in the same direction with a speed of 30kmh−1 . They are separated from each other by 5 km. Third car moving in the opposite direction meets the two cars after an interval of 4 min. What is the speed of the third car?

Question : Two cars are moving in the same direction with a speed of 30kmh−1 . They are separated from each other by 5 km. Third car moving in the opposite direction meets the two cars after an interval of 4 min. What is the speed of the third car?

(A) $30kmh^{-1}$

(B) $35kmh^{-1}$

(C) $40kmh^{-1}$

(D) $45kmh^{-1}$