Air-petrol ratio in an automotive petrol engine is around

ANS:A - 14 : 1

The air-fuel ratio in an automotive petrol engine typically falls around 14 : 1. This means that for every 14 parts of air, there is 1 part of petrol (or gasoline) by mass. This ratio is commonly referred to as the stoichiometric ratio, where there is just enough air to completely burn all the fuel without any excess oxygen or unburned fuel remaining after combustion.