9 . What is the IUPAC name for the following structure?(A) 2,5-dimethylheptane
(B) 2-ethyl-5-methylhexane
(C) 3,6-dimethylheptane
(D) 5-ethyl-2-methylhexane
10 . What is the IUPAC name for the following structure?(A) 4-isopropyl-2-methylhexane
(B) 3-isopropyl-5-methylhexane
(C) 2,2,5-trimethyl-3-ethylhexane
(D) 3-ethyl-2,2,5-trimethylhexane
11 . The IUPAC name for the following structure starts with what prefix?