Give the value of rest potential in a polarized muscle fibre.

Explanation

**Step-by-Step Solution:**

1. **Understanding Resting Potential**: Resting potential refers to the electrical potential difference across the membrane of a muscle fiber when it is not actively contracting. This state is crucial for the muscle fiber to respond to stimuli.

2. **Ion Concentration**: In a polarized muscle fiber at rest, there is a higher concentration of potassium ions (K⁺) inside the cell (exoplasm) and a higher concentration of sodium ions (Na⁺) outside the cell.

3. **Movement of Ions**: During the resting state, potassium ions tend to move out of the cell more rapidly than sodium ions move into the cell. This movement is primarily due to the permeability of the cell membrane and the action of ion channels.

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