What is an error? What are constant errors?

Explanation

### Step-by-Step Solution

**Step 1: Define Error**
- An error in measurements refers to the uncertainty or the deviation from the true value of a physical quantity. It indicates how much the measured value may differ from the actual value.

**Step 2: Explain the Concept of Error with an Example**
- For example, if you are using a scale that measures in millimeters, the smallest unit you can measure is 1 mm. If you attempt to measure a length and report it as 4.12 cm, the precision of your measurement is limited by the scale. If the scale can only accurately measure to the nearest 0.1 cm, then any value you report may have an error margin, such as 0.02 cm.

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