Which of the following compounds can exist as enantiomers? check all that apply.
Cl
a. CH₃CH₂|CH₂CH₂CH₃
Br

b. CH₃CH₂|CHCH₃
CH₃

c. CH₃CH₂|CHCH₂CH₃
Br

d. CH₂=CH|CHCH₃
NO₂

e. CH₃CH₂|CHCH₃
Cl

f. CH₃CH₂SH