How many structurally isomeric dibromo butanes are possible.

How many structural isomeric ethers are possible with molecular formula C_(5)H_(12) O ?

How many structural isomers are possible for butane?

How many structurally isomeric cyclic isomers of molecular formula C_(3)H_(7)N are possible:

How many structurally isomeric cyclic isomers of molecular formula C_(3)H_(7)N are possible:

How many structural isomeric alkene possible for molecule formula C_5H_10 which can show geometrical isomerism ?

How many structural isomeric alkene possible for molecule formula C_5H_10 which can show geometrical isomerism ?