In the first round of math contest, each students had to answer 2 questions. Miriam averaged 76 seconds per question. Jake and Rafael averaged 84 seconds per question, and Sam averaged 80 seconds per question. At the end of the first round, what was the total time for all 4 students?
a) 324 seconds
b) 400 seconds
c) 480 seconds
d) 568 seconds
e) 648 seconds