The theoretically correct air fuel ratio for petrol engine is of the order of___________________?
A. 6 : 1
B. 9 : 1
C. 12 : 1
D. 15 : 1
E. 20 : 1
A. 6 : 1
B. 9 : 1
C. 12 : 1
D. 15 : 1
E. 20 : 1