Some of the other material in that link is rather poor also - has all the hallmarks of keen amateurs. If there are specified training outcomes, how is it that the material has not been properly checked?
Apart from spelling errors - and apostrophes! - the illustration of the 4-stroke cycle is also wrong. The whole lot suffers from typical PowerPoint Problem, that the originators do not have clearly in their minds whether it is supposed to be a set of visual aids to teaching, or a set of DIY learning material.
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