Write 0.8 in simplest form fraction

Which of the following would be a good name for the function that takes the weight of a box and returns the energy needed to lift it?

How many different three-digit numbers can be formed using the digits 1 comma 2 comma 9 comma 6 comma 4 comma 3 comma and 8 without repetition? for example, 664 is not allowed.

What is the image of c for a 90° counterclockwise rotation about a? (3, 7) (-1, 3) (7, 3)