Provide a line drawing and the molecular formula for the following: (a) A linear alkyne with three carbon atoms and one triple bond, (b) A linear alkene with four carbon atoms and one double bond, (c) A cyclic alkene with five carbon atoms in a ring and two double bonds.

Alkynes are hydrocarbons that contain at least one carbon-carbon triple bond. They follow the general formula CnH2n-2, where 'n' is the number of carbon atoms. In the case of a linear alkyne with three carbon atoms, the molecular formula would be C3H4, and its structure would show a straight chain with a triple bond between the first and second carbon atoms.

Alkenes are unsaturated hydrocarbons characterized by at least one carbon-carbon double bond. They adhere to the general formula CnH2n, indicating that for every 'n' carbon atoms, there are '2n' hydrogen atoms. For a linear alkene with four carbon atoms, the molecular formula is C4H8, and the structure will depict a straight chain with a double bond between two of the carbon atoms.

Cyclic alkenes are alkenes that form a ring structure and contain at least one double bond. The general formula for cyclic alkenes is CnH2n-2, similar to that of alkynes, but they differ in structure. For a cyclic alkene with five carbon atoms and two double bonds, the molecular formula would be C5H6, and the structure would illustrate a five-membered ring with two double bonds positioned between the carbon atoms.