<span>During the stage of internal combustion engine operation in which the piston rises and compresses the fuel in the combustion chamber, the intake and exhaust valves will both be closed. This means that the mixture of fuel and air are compressed, due to the seal around the combustion chamber that has been created by the closure of both of these valves. Hopefully that answered your question for you!</span>
The correct Answer is A. Crude oil and coal together account for more than half of the world’s energy.
Sorry dude..
I don't know from where u got this question but I wasn't able to get the answer from nowhere..!!
hmm..
