4. Construct models for both R-2-chlorobutane and its enantiomer S-2-chlorobutane. For each of the types of structures shown, fill in the necessary atoms to draw both stereoisomeers. Wedge Newman Fischer (R)-2-chlorobutane H CI CH3 H CH3 f CHCH3 (S)-2-chlorobutane I CI H I CH3 CH3 CHCH3