Answer: 3.16

The standard error of the sample mean is calculated as: **Standard Error = Population Standard Deviation / √Sample Size** Given: - Population standard deviation (σ) = 100 - Sample size (n) = 1,000 Calculation: √1,000 ≈ 31.6228 Standard Error = 100 / 31.6228 ≈ 3.16228 ≈ 3.16 **Why other options are incorrect:** - **A (0.1)**: This would be 100/1,000, which is incorrect because we need to divide by the square root of the sample size, not the sample size itself. - **C (27.6)**: This is too large and doesn't correspond to any standard calculation. - **D (0.01)**: This would be 100/10,000, which incorrectly uses the population size instead of the sample size. **Key Concept:** The standard error measures the precision of the sample mean as an estimate of the population mean. As sample size increases, the standard error decreases, making the sample mean a more precise estimate of the population mean.

Author: Nikitesh Somanthe