Many ! plz! i need ! which one of the following determines the ability of a diesel engine to start at low temperatures, providing smooth warm-up and even combustion? a. specific gravity rating b. cloud point c. sulfur content d. cetane rating

Cetane rating of the diesel ensures the low temperature and uniform combustion. Centane number is just opposite to the octane number of petrol engine, cetane number of diesel determines at which temperature the diesel will going to autoignite.

d. air pressure decreases as altitude increases.