Various masaail of fasting

Q: I live in the north of Finland. The sun rises at 02.30 am and sets at 10.35 pm. Do I have to fast for over twenty hours? 

Q: I would like to keep all my fast in Ramadhaan. Am i allowed to take a contraceptive pill for the month, to prevent me from getting my period?

Q: Please explain what is forbidden during the holy month of Ramadhaan between husband and wife?