music: 60's Chart Toppers: Name The Artist: Don't Worry?

Questions

although his career was snuffed out in the same plane crash that killed buddy holly, which east l.a kid had a memorable top ten hit about his girlfriend donna?

patsy cline is the most noted with pop-country crossovers. which other singer should not be overlooked for her hits 'break it to me gently' and 'fool no. 1'?

the fireballs had some success with the record 'torquay', but when they teamed up with jimmy gilmer, which record stayed at no. 1 for an entire year?

although they recorded more that should have been u.s hits, 'tell her no', 'time of the season' and 'she's not there were the only ones to make it to the u.s top ten for which band?

who started on the san francisco scene with 'oh well', but are probably best known for their album 'rumors'?