What does the mechanical advantage of a first class lever depend upon? Describe how it can be changed.

Explanation

### Step-by-Step Solution:

1. **Understanding First Class Levers**:
- A first class lever is a type of lever where the fulcrum is positioned between the effort (force) and the load (weight).

2. **Mechanical Advantage Definition**:
- The mechanical advantage (MA) of a lever is defined as the ratio of the load force to the effort force. It indicates how much the lever amplifies the input force.

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