I just cannot figure out if these answers are correct or not. Can you please help me?

78. If the sound system hadn’t failed, last night’s show would have been better.

This is a correct sentence using the 1st conditional form.

x This is a correct sentence using the 2nd conditional form.

This is a correct sentence using the 3rd conditional form.

This is an incorrect sentence.

79. They’ll work on new songs tomorrow if they would have time.

This is a correct sentence using the 1st conditional form.

x This is a correct sentence using the 2nd conditional form.

This is a correct sentence using the 3rd conditional form.

This is an incorrect sentence.

80. If the club’s manager agrees, they’ll play a few more original songs next time.

This is a correct sentence using the 1st conditional form.

This is a correct sentence using the 2nd conditional form.

x This is a correct sentence using the 3rd conditional form.

This is an incorrect sentence.

81. The duo could perform at weddings if Mike played the flute.

This is a correct sentence using the 1st conditional form.

x This is a correct sentence using the 2nd conditional form.

This is a correct sentence using the 3rd conditional form.

This is an incorrect sentence.

2 answers

http://grammar.ccc.commnet.edu/grammar/conditional2.htm

Study this webpage, and then rethink your answers.
A person with brown hair may also exhibit the trait of brown eye color.