PLEASE HELP

I don't understand almost any of this, the one I'm having the most trouble with is 4.

S. Ruble/$ = Ruble 5/$ F, Ruble$ = Ruble 6/$ 1. Is the ruble selling at a forward premium or discount? By how much? S, DKK/$ = DKK5/$ S.DKK/$ = DKK8/$, 2. What is the percentage change in the nominal value of the DKK (SSIDKK)? 3. What about $ value (s DKK$)? 4. Does (1+sait) = 1/(1+stid) hold? Show your work. S. Ruble/$ = Ruble 5/$ F, Ruble$ = Ruble 6/$ 1. Is the ruble selling at a forward premium or discount? By how much? S, DKK/$ = DKK5/$ S.DKK/$ = DKK8/$, 2. What is the percentage change in the nominal value of the DKK (SSIDKK)? 3. What about $ value (s DKK$)? 4. Does (1+sait) = 1/(1+stid) hold? Show your work