CH2 – CH3 | a) CH3 – CH – CH –CH2 – CH = CH2 | CH3
Объяснение:
CH3-CH (CH3) - CH (CH3) 2
(CH3) 2CH-CH2-CH (CH3) 2
CH3-CH (CH3) - C (CH3) 3
CH3-CH (CH3) - CH2-CH3