To which wire of a cable in a power circuit should the metal case of a geyser be connected?

Explanation

To determine which wire of a cable in a power circuit the metal case of a geyser should be connected to, we can follow these steps:

### Step 1: Understand the Wiring System
In a typical electrical wiring system, there are usually three types of wires: live (often brown or red), neutral (often blue or black), and earth (often green or yellow-green).

### Step 2: Identify the Purpose of Each Wire
- **Live Wire**: Carries current to the appliance.
- **Neutral Wire**: Completes the circuit by carrying current away from the appliance.
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