Give the IUPAC names of the following:
(i) `CH_(3)-underset(CO_(2)H)underset(|)(C)H-CH_(2)-CH_(3)`
(ii) `CH_(3)-underset(OH)underset(|)(C)H-CH_(2)-COOH`
(iii) `CH_(3)COCH_(2)COOH`
(iv) `CHO.COOH`
(v) `CH_(3)COCOOH`
(vi) `C_(6)H_(5)-CH=CH-COOH`
(vii) `C_(6)H_(5)CH_(2)CH_(2)COOH`
(viii) `CH_(3)CH_(2)CH(CHO)CH_(2)COOH`
(ix) `CH_(3)CH(Br)CH_(2)CONHCH_(3)`

Explanation

(i) 2-Methylbutanoic acid, (ii) 3-Hydroxybutanoic acid, (iii) 3-Oxobutanoic acid, (iv) 2-Oxoethanoic acid, (v) 2-Oxopropanoic acid, (vi) 3-Phenylbut-2-en-1-oic acid, (vii) 3-Phenylpropanoic acid, (viii) 3-Ethyl-4-oxobutanoic acid (ix) 3-Bromo-N-methylbutanamide.