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.

Verified step by step guidance

1. Step 1: Identify the structure of the linear alkyne with three carbon atoms. An alkyne is a hydrocarbon with at least one carbon-carbon triple bond. For three carbon atoms, the structure is HC≡C-CH₃, and the molecular formula is C₃H₄.
2. Step 2: Draw the line structure for the linear alkyne. In line structures, each vertex represents a carbon atom, and lines represent bonds. For HC≡C-CH₃, draw a line with three vertices, with a triple bond between the first two vertices.
3. Step 3: Identify the structure of the linear alkene with four carbon atoms. An alkene is a hydrocarbon with at least one carbon-carbon double bond. For four carbon atoms, the structure is CH₂=CH-CH₂-CH₃, and the molecular formula is C₄H₈.
4. Step 4: Draw the line structure for the linear alkene. For CH₂=CH-CH₂-CH₃, draw a line with four vertices, with a double bond between the first two vertices.
5. Step 5: Identify the structure of the cyclic alkene with five carbon atoms and two double bonds. A cyclic alkene is a ring structure with at least one double bond. For five carbon atoms, the structure is cyclopentadiene, with the molecular formula C₅H₆.