Everything that they teach a M.E. major in university

[Ranger Mike]

Upon completion you will know why cow magnets taped to your automobiles fuel line will add 2 to 5 miles per gallon fuel milage to any automobile!

https://www.magnetsource.com/collections/cow-magnets-l1

but I digress!!
this was a thing in the oil embargo in 1970s
no shi#!