How many quarter litres are contained in 20 litre jerrycan?

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

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

Which equation represents h for right triangle abc