What is the systematic name for the following structure, specifying cis-/trans-?
cis-2,3-diethyl-2-butene
cis-3,4-dimethyl-3-hexene
trans-4-ethyl-3-methyl-3-pentene
trans-3-methyl-2-ethyl-2-pentene
cis-dimethyl-cis-diethyloctene
