....(NO LINKS)...they r not optical isomers, they r geometrical..NOW JUST TELL ME WHICH ARE CIS AND WHICH ARE TRANS.....NO LINKS...(DO CIS-TRANS IS ALLOWED IN THE SAME COMPOUND AT THE SAME TIME...LIKE IN THE LAST TWO COMPOUNDS)

....(NO LINKS)...they r not optical isomers, they r geometrical..NOW JUST TELL ME WHICH ARE CIS AND WHICH ARE TRANS.....NO LINKS...(DO CIS-TRANS IS ALLOWED IN THE SAME COMPOUND AT THE SAME TIME...LIKE IN THE LAST TWO COMPOUNDS) (iii) NH3 NH3 NH3

Dear Student

Trans-isomers are optically inactive
Cis-isomers are optically active and show optical isomerism

The first image will be cis, it will produce optically identical image or mirror image.


Second is also cis and the last two are trans.

Mentioned below are the images of the compound, which shows
trans -Cl
trans- NH₃ 
both sets can be Mutually cis, 
and
these can also exist as optical isomers.




Yes, trans and cis can both exist in the same compound. This can be elaborated through an example -
[Co(en)(NH₃)₂Cl₂]²⁺



Regards