Hello again. On the cadence question where you have to specify the chords to use, is it enough just to write I, II, V etc or do you also have to add "C major", "D minor" etc? The answer booklet has both written down but I don't know if it is an either/or situation. Thanks.

The question on the paper will tell you what optioons you have.
Usually the choice is write the notes on the stave OR use I, IV V etc. OR any other recognised symbols.

either will do.

You may write in Roman no or alphabets or notes in the stave, whatever you like.