State one relevant observation for the reaction
Sulphide ore is added to a tank containing oil and water, and then stirred or agitated with air.

Explanation

To solve the question, we need to state one relevant observation for the reaction when sulphide ore is added to a tank containing oil and water, and then stirred or agitated with air.

### Step-by-Step Solution:

1. **Understanding the Components**:
- We have sulphide ore, oil (usually pine oil), and water in a tank.
- Sulphide ore contains valuable minerals that we want to concentrate.

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