Hui challenged Feng to a marathon race (42 kilometers). Hui was so confident that he even gave Feng a 30-minute head start. Feng runs the race at a rate of 6 kilometers per hour. Hui runs the race at a rate of 7 kilometers per hour. If Hui and Feng start from the same point and follow the same path, how long will Hui run before he overtakes Feng?
A. 2.5 hours
B. 3 hours
C. 4.25 hours
D. 3.75 hours
E. 5 hours
A. 2.5 hours
B. 3 hours
C. 4.25 hours
D. 3.75 hours
E. 5 hours
The more you suffer before the test, the less you will do so in the test! 
