Complete the following:

Explanation

To complete the reaction as described in the video transcript, we can break down the process into clear steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: We start with a cyclic ether and ethanol (C2H5OH) as our base. The cyclic ether has a ring structure that creates strain, making it reactive.

2. **Nucleophilic Attack**: The oxygen atom in ethanol (C2H5OH) acts as a nucleophile. It attacks one of the carbon atoms in the cyclic ether. This attack is facilitated by the ring strain present in the cyclic ether.

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