Read the following email message. Complete the email by filling in the blanks. Select the best choice for each blank.

Hi Professor Johnson, I'm working on my maritime history presentation about Viking ships, and I found some interesting information at the Viking Heritage Museum. The Vikings had two main types of ships: the longship for warfare, which could hold 1......, and the knarr for trading, which could carry 2....... What fascinated me most was their navigation system. While modern ships rely on GPS, Vikings used tools like 3...... to determine their direction. They were quite strategic about their sailing schedule too, preferring to voyage during 4...... when conditions were optimal. I was surprised to learn that crew members needed to meet certain requirements, including 5....... Would you be available to discuss these findings further? Best regards,Sarah

Choose the best option.

The main difference between longships and knarr was their 1....... The Vikings' ship construction technique was specially designed to 2....... Winter sailing was 3.......