Ignition lag is__________________?

Ignition lag is__________________?

A. the time taken by fuel after injection (before top dead center) to reach upto auto-ignition temperature
B. time before actual fuel injection and the pump plunger starts to pump fuel
C. time corresponding to actual injection and top dead center
D. time corresopnding to actual ingition and top dead center
E. none of the above

Cetane___________________?

Cetane___________________?

A. has zero cetane number
B. has 100 cetane number
C. helps detonation
D. is a straight chain paraffin
E. determines the efficiency of an I.C. engine

Iso-oct ,ne________________?

Iso-oct ,ne________________?

A. has octane number of 0
B. has octane number of 50
C. has octane number of 100
D. is an index of detonation quality
E. is an index of knocking quality