A : In a measurement, two readings obtained are 20.004 and 20.0004. The second measurement is more precise.
R : Measurement having more decimal places is more precise.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To solve the question, we need to analyze the assertion (A) and the reason (R) provided.

### Step 1: Understand the Assertion (A)
The assertion states that the second measurement (20.0004) is more precise than the first measurement (20.004).

### Step 2: Understand the Reason (R)
The reason states that a measurement with more decimal places is considered more precise.

### Step 3: Compare the Measurements
- The first measurement is **20.004**, which has **three decimal places**.
- The second measurement is **20.0004**, which has **four decimal places**.

### Step 4: Analyze Precision
Precision in measurements refers to the degree of reproducibility or exactness of the measurement. A measurement with more decimal places indicates a finer level of detail and thus is generally considered more precise.

### Step 5: Conclusion
Since the second measurement (20.0004) has more decimal places than the first measurement (20.004), it is indeed more precise. Therefore, both the assertion (A) and the reason (R) are correct, and the reason correctly explains the assertion.

### Final Answer
Both the assertion (A) and the reason (R) are correct, and the reason correctly explains the assertion.

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