Auto-ignition reaction time for petrol engine first decreases with increase in fuel air ratio, reaches a minimum value and then increases with subsequent increase in fuel air ratio. The minimum value occurs in the region of________________?

Auto-ignition reaction time for petrol engine first decreases with increase in fuel air ratio, reaches a minimum value and then increases with subsequent increase in fuel air ratio. The minimum value occurs in the region of________________?

A. Lean mixture
B. Chemically correct fuel air ratio
C. Rich mixture
D. Unpredictable

The specific fuel consumption for a petrol engine first decreases with increase in fuel air ratio and then increases with further increase in fuel air ratio. The minimum value occurs in the range of__________________?

The specific fuel consumption for a petrol engine first decreases with increase in fuel air ratio and then increases with further increase in fuel air ratio. The minimum value occurs in the range of__________________?

A. lean mixture
B. chemically correct mixture
C. rich mixture
D. unpredictable
E. none of the above