Which alloy is generally used in making bullets, shells and lighter flints? What is its composition ? With which other element it is generally alloyed and why ?

Explanation

### Step-by-Step Solution:

1. **Identify the Alloy**: The alloy commonly used in making bullets, shells, and lighter flints is called **Mischmetall**.

2. **Composition of Mischmetall**: Mischmetall is primarily composed of a mixture of rare earth metals. The typical composition includes:
- **Lanthanum (La)**: 25-35%
- **Cerium (Ce)**: 50-60%
- **Neodymium (Nd)**: 5-10%
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