What is the E/Z configuration of cyclic compounds?
What is the meaning of cis and trans?
cis means on the same side (or face), trans means on the opposite side (or face).
Can I use cis and trans for cylic compounds?
Yes, you can describe the relative orientation of substituents on a ring using cis and trans, such as in the case of 1,3-dibromcyclohexane.

Can I use cis and trans for alkenes?
Yes, in priciple. But you should rather use E and Z. Note that these descriptors are taken from German.

E means entgegen and refers to opposite directions (or sites), while Z means zusammen, which is together, that is the same direction (or site).
What about the compounds in my question?
E/Z or cis/trans are not applicable here.
In the first case, the $\ce{Br}$ atom is in the ring plane, the methyl group can be above or below it. You could describe the absolute stereochemistry at the centre bearing the $\ce{CH3}$ substituent using R or S.
In the second case, there's no alkene at all but a disubstituted benzene. The relative orientation of the substituents on these systems can be described by assigning the proper numbers or by using the ortho- meta- or para-prefix. For this compounds, 2-isopropylnitrobenzene or o-isopropylnitrobenzene would be ok.