The bottom compound has bromine and an R group connected to one of its SP2 double bond carbons, and chlorine and the same R group connected to the other. This fact, it would seem, indicates cis-trans isomerism.
The top compound has a methyl group and an R group connected to one of its SP2 double bond carbons, and a hydrogen atom and a different R' group connected to the other. Conversely, it appears that this precludes cis-trans isomerism.
First, Why does the top compound has geometric isomerism while the bottom compound doesn't given these facts?
Secondly, given that benzene is planar and its substituents and hydrogen atoms are level with the plane of the ring, are the methyl group and the hydrogen atom around the double bond of the top compound also flatly level as in benzene, or are they equatorial like in cyclohexane, slating above or under the plane of the ring?