1)Составьте формулы: а) 4,4,5-триметилгексановая кислота 2)Дайте название следующему продукту по систематической номенклатуре:
CH2-CH3 O
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CH3-C-CH2-CH2-C
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C=CH H
a)3-метил-3- этил-1-гексиналь
b)4-метил-4-этил-5-гексиналь
в)2-этил-2-этинилпенталь
г)4-метил-4-этинилгексаналь
I haven't seen him for ages
He has been doing his lessons since lunch.
I haven't heard about him for a long time.
I have been driving since I was 17.
Jack has failed his driving test three times because he doesn't know how to park.
I think he has made a lot of improvement.
Alice hasn't passed her driving test because she doesn’t know the rules well.
She has been worrying about this for two months.
She has been studying the driver’s manual for hours every day.
She hasn't taken another test yet.
I have had a headache since I got up.
He is my friend, I have known him for a long time.
Ivan has a stomachacke. He has been eating junk food all day.
I have never heard that song before.
ответ:I haven't seen him for ages
He has been doing his lessons since lunch.
I haven't heard about him for a long time.
I have been driving since I was 17.
Jack has failed his driving test three times because he doesn't know how to park.
I think he has made a lot of improvement.
Alice hasn't passed her driving test because she doesn’t know the rules well.
She has been worrying about this for two months.
She has been studying the driver’s manual for hours every day.
She hasn't taken another test yet.
I have had a headache since I got up.
He is my friend, I have known him for a long time.
Ivan has a stomachacke. He has been eating junk food all day.
I have never heard that song before.