Identify the longest continuous carbon chain that includes the double bond.

To name the compound, we follow the IUPAC rules for alkenes:

Step 1: Identify the longest continuous carbon chain that includes the double bond.
Let's redraw the structure to clearly see the carbon chain and substituents.
The central double bond is between two carbon atoms.

• The carbon on the left side of the double bond is bonded to a methyl ($\text{CH}_3$) group (upwards) and an ethyl ($\text{CH}_2\text{CH}_3$) group (leftwards).
• The carbon on the right side of the double bond is bonded to an ethyl ($\text{CH}_2\text{CH}_3$) group (rightwards) and an ethyl ($\text{