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The depth of a lake at a certain point, wich is a function of the distance of that point from shore, is 30 feet.

The final cost of a sale is determined by multiplying the price on the tag by 75%. which best describes the function that represents the situation?

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible