draw the following branched alkanes:\n4 - ethyl - octane\n2 - methyl - nonane\n3 - ethyl - 2,2 - dimethyl…

Explanation:

Step1: Analyze 4 - ethyl - octane

Octane has 8 - carbon main chain. Ethyl group ($-C_2H_5$) is attached at 4 - th carbon. $CH_3CH_2CH_2CH(CH_2CH_3)CH_2CH_2CH_2CH_3$

Step2: Analyze 2 - methyl - nonane

Nonane has 9 - carbon main chain. Methyl group ($-CH_3$) is attached at 2 - nd carbon. $CH_3CH(CH_3)CH_2CH_2CH_2CH_2CH_2CH_2CH_3$

Step3: Analyze 3 - ethyl - 2,2 - dimethyl - hexane

Hexane has 6 - carbon main chain. Two methyl groups ($-CH_3$) are at 2 - nd carbon and an ethyl group ($-C_2H_5$) is at 3 - rd carbon. $CH_3C(CH_3)_2CH(CH_2CH_3)CH_2CH_3$

Step4: Analyze 3,3 - dimethyl - pentane

Pentane has 5 - carbon main chain. Two methyl groups ($-CH_3$) are at 3 - rd carbon. $CH_3CH_2C(CH_3)_2CH_2CH_3$

Answer:

For 4 - ethyl - octane: $CH_3CH_2CH_2CH(CH_2CH_3)CH_2CH_2CH_2CH_3$ For 2 - methyl - nonane: $CH_3CH(CH_3)CH_2CH_2CH_2CH_2CH_2CH_2CH_3$ For 3 - ethyl - 2,2 - dimethyl - hexane: $CH_3C(CH_3)_2CH(CH_2CH_3)CH_2CH_3$ For 3,3 - dimethyl - pentane: $CH_3CH_2C(CH_3)_2CH_2CH_3$