Task: Question Answering
Input (English): Question: Mike drives his new Corvette from San Francisco to Las Vegas, a journey of 640 miles. He drives the first half of the trip at an average rate of 80 miles per hour, but has to slow down for the second half of his journey. If the second half of the trip takes him 200 percent longer than the first half, what is his average rate J in miles per hour for the entire trip?

 Option A: 26.7

 Option B: J=30.0

 Option C: J=40.0

 Option D: J=53.3

 Option E: 60
Output (English): Option C