Add spaces: Atthepeninsula,itmergesagainwiththefreightline,andfromheretherailwayforbothpassengerandfreighttrainsrunsonthesametrackdownintotheØresundtunnelunderDrogden.

Answer: At the peninsula, it merges again with the freight line, and from here the railway for both passenger and freight trains runs on the same track down into the Øresund tunnel under Drogden.

Add spaces: Theonlythingthatmattersisthegapbetweenthedomesticandforeigninterestratesandnotitsabsolutevalue.

Answer: The only thing that matters is the gap between the domestic and foreign interest rates and not its absolute value.

Add spaces: ItprovedtobeaGuillemotoftheArcticsubspeciesCepphusgryllemandtii,whoserangeisfromCanadatoSvalbard,NorthSiberiaandNorthAlaska.

Answer:
It proved to be a Guillemot of the Arctic subspecies Cepphus grylle mandtii, whose range is from Canada to Svalbard, North Siberia and North Alaska.