10. Which type of sampling technique involves dividing the population into non-overlapping subgroups and then randomly selecting samples from each subgroup? a) Simple random sampling b) Systematic sampling c) Stratified sampling d) Cluster sampling 1. What does the p-value represent in hypothesis testing? a) The probability of making a Type I error b) The probability of making a Type II error c) The probability of observing the data if the null hypothesis is true d) The level of confidence in the alternative hypothesis 2. What is the formula for calculating the standard deviation of a dataset? a) (Sum of values) / (Number of values) b) Square root of the mean c) (Sum of squared differences from the mean) / (Number of values) d) Median - Mode 3. In a normal distribution, what percentage of data falls within two standard deviations of the mean? a) 25% b) 50% c) 68% d) 95%