Which of foe following represents foe correct IUPAC name for foe compounds concerned:

Which of foe following represents foe correct IUPAC name for foe compounds concerned:
(a) 2,2-Dimefoylpentane or 2-Dimefoyl-pentane.
(b) 2,4,7-Trimefoyloctane or 2,5,7-Trimefoy-1 oc¬tane.
© 2-chloro-4-methylpentaneor4-chloro-2-meth-ylpentane.

(a)2,2-Dimethylpentane
(b) 2,4,7-lnmethyloctane
© 2-chloro-4-methylpentane