commerce 2ma3-- for the pre-req can we be registered in 1b03 or have to ahve already taken it?

another note-- econ 1b03 wont let me change it from semester 2 day to semester 1 evening?? it says this:

This change is exactly the same as the original assignment. If you want to reinstate this assignment, please press undo button to bring the course back to the change area and then select undo from the action dropdown box for the modifying course.

You need to already have taken 1B03.. and you need a 7 in it.
Not sure about the second thing though.