The speed of a car is 50 km in the first hour and 60 km in the second hour. What is the average speed of the car?  Choose the correct answer:
A) 79 kmph
B) 85 kmph
C) 55 kmph
D) 23 kmph
E) 14 kmph

Rationale: "s = ( 55 + 60 ) / 2 = 55 kmph answer : c"
Answer: C