16. What is the correct structure for (2S,5R)-2-fluoro-5-methylnonane?
A) I
B) II
C) III
D) IV
17. Rank the compounds shown from most (fastest) to least (slowest) reactive in an $S_N2$ reaction.
I. (structure of 1-bromopropane)
II. $CH_3Br$
III. (structure of bromobenzene)
IV. (structure of 2-bromopropane)
A) I > IV > II > III
B) II > I > IV > III
C) III > IV > I > II
D) IV > I > II > III
E) IV > III > I > II