Usually, the egg will be implanted between 6 to 12 days of egg retrieval. After five days of embryo transfer, the egg reaches blastocyst stage. For accuracy, you need to county the day of retrieval as day 0.
A motor car engine is an Internal Combustion Engine (ICE). Energy is created by burning either diesel or petrol in a combustion chamber. In such an engine, the energy is transferred from the pistons moving up and down at high speeds. This up-down motion is converted to a rotary motion through the crankshaft and axle.
common answer is that the engine makes the car go forward but, it is the engine that makes the wheels go around but if the tires are on slick ice or deep mud, they just spin. Friction is also needed.