Final answer:
The subject matter pertains to college-level statistics, covering normal distribution, hypothesis testing, and sample mean calculations used to infer population characteristics.
Step-by-step explanation:
The subject question relates to probability and statistics, specifically to the concepts of normal distribution, hypothesis testing, and sample mean calculations. The scenarios provided involve understanding the properties of the normal distribution, such as the standard deviation and mean, and applying statistical tests to determine probabilities and test hypotheses about population means based on sample data. In each instance, students are required to use statistical methods to analyze data and draw conclusions from samples to infer characteristics of wider populations.