Coal mining has been known, since

Options

A. 1750 AD
B. 675 AD
C. Roman times
D. Mediaeval times.

Answer

To solve the question "Coal mining has been known since," we will analyze the options provided and determine the correct answer step by step.

### Step 1: Understand the Question
The question asks for the historical timeline of coal mining, specifically when it first began.

### Step 2: Analyze the Options
The options given are:
1. 1750 AD
2. 675 AD
3. Roman times
4. Medieval times

### Step 3: Research Historical Context
Coal mining has a long history. It is known that:
- Coal mining was practiced in ancient civilizations, notably in ancient China and during the Roman Empire.
- The Roman Empire's coal mining activities occurred between 43 AD and 410 AD.

### Step 4: Evaluate Each Option
- **1750 AD**: This is too late, as coal mining was already known before this date.
- **675 AD**: This is also too late, as coal mining began much earlier.
- **Roman times**: This is a valid option since coal mining was practiced during the Roman Empire.
- **Medieval times**: While coal mining continued during the medieval period, it was not the initial period when it was known.

### Step 5: Conclusion
Based on the historical context, the correct answer is **Roman times**.

### Final Answer
The correct answer is: **Roman times**.

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