Detailed Instructions: In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
Q: Problem: john goes to his office by car at a speed of 40 kmph and reaches 8 minutes earlier . if he goes at a speed of 30 kmph , he reaches 4 mins late . what is the distance from his house to office ?
Options: a ) 18 km , b ) 20 km , c ) 22 km , d ) 24 km , e ) 30 km
A:
d