Where does the salivary duct open in cockroach?

Explanation

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about the location where the salivary duct opens in a cockroach. To answer this, we need to understand the anatomy of the cockroach, specifically the salivary glands and their ducts.

2. **Locate the Salivary Glands**: Cockroaches have salivary glands that produce saliva. These glands are connected to ducts that transport saliva to the mouth.

3. **Understand the Ducts**: There are two main ducts associated with the salivary glands in cockroaches: the common salivary duct and the efferent salivary duct.

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