Based on the clue 'bjarni herjulfsson may have been the first to sigh...', what is the answer?

What is associated with: bizet served in the national guard to protect paris from a siege of the city during this 1870… Based on the clue 'bizet wrote as for this austrian surprise symphony...', what is the answer? What is referred to by 'bizets carmen for example'? What is associated with: bjarni herjolfsson sold his ship to this man who used it to explore vinland around 1000? Based on the clue 'bjork the former lead singer of this icelandic gro...', what is the answer? What is referred to by 'bjork'? What is associated with: bjorn borg stefan edberg helped this country reach the davis cup finals 7 times in the 1980s? Based on the clue 'bjorn borg won his first wimbledon but this americ...', what is the answer?