Which is the correct way to write this phrase? (three weeks’ supply) (three weekses’ supply) (three weeks supply) (three week’s supply)

The correct way to write that pharse is three weeks' supply.

1- cleans/ tidies up

2- were

3-would be

4- had known

5-takes

6-must be/ have to be/should be

in this alternate universe, renaissance romeo is now seventeen, an apprentice to a glass maker in venice. modern romeo is planning to go to college. what major do you think he’ll elect?