Write the IUPAC name of the following compound:
` CH_3 - underset(C_2 H_5) underset(|)(CH) - overset(CH_3) overset(|)CH -CH_2 -CH =CH_2`

Explanation

To derive the IUPAC name of the given compound, we will follow these steps:

### Step 1: Identify the Longest Carbon Chain
First, we need to identify the longest continuous carbon chain in the compound. In this case, we can see that the longest chain consists of 7 carbon atoms.

### Step 2: Number the Carbon Chain
Next, we will number the carbon chain. We will start numbering from the end closest to the double bond to give it the lowest possible number.

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