For each of the compounds described by the following names,
1. Draw a three-dimensional representation.
2. Star each chirality center.
3. Draw any planes of symmetry.
4. Draw any enantiomer.
5. Draw any diastereomers.
6. Label each structure you have drawn as chiral or achiral.
(a) (S)-2-chlorobutane
(b) (R)-1,1,2-trimethylcyclohexane