I. Answer all the following

1. What are the compression ratio for S.I and C.I engines
2. Define Scavenging
3. What is meant by Pre-Ignition?
4. List out any two factors affecting the ignition lag
5. What is lean mixture

II. answer from the following 

1. If the combustion takes place inside the engine than it is called__________________
2. If the combustion takes place outside the engine than it is called __________________
3. In a 4-stroke engine the working cycle is completed in ____ revolutions of crankshaft
4. In a 2-stroke engine the working cycle is completed in ____ revolutions of crankshaft
5. In a 4-stroke engine ___________ are used
6. In a 2-stroke engine __________ are used
7. A device which converts one form of energy to other is called ____________
8. During suction __________ valve remains in open position
9. During exhaust ___________ valve remains in open position
10. Speed of camshaft is ____________