Quick question on currencies

This part is crazy, please help me confirm this points if my understanding is correct or not?

1-Unhedged return = R_FX + expected change in S or expected change in interest

-Hedge return = R_FX + forward discount/premium

Forward discount/premium calculate precisely = F – s / s (if its given), if approximate = interest differential

2-IT seems that there is no positive/negative carry trade in the content this year, was it dropped? IF not, what are they exactly?

3-Roll yield = F-s /s , will be positive for short position and reduce hedging cost, negative for long position (of base currency). correct?

4-Total return = R_FC + R_FX

For a portfolio of bond/stock, R_FC is given, being the return of foreign assets and based on foreign currency return

For a portfolio of bond, stock , future, we need to convert back to domestic currency?

Thanks a lot