Final answer:
The question is about applying statistical methods to predict outcomes based on random variables, focusing on college-level probability and statistics.
Step-by-step explanation:
The question involves understanding and analyzing random variables in statistical studies. In the given context, x represents the number of trees per mile on selected streets, which can be understood as discrete data, given typical urban planning metrics.
The term y corresponds to the average speed of cars, which is likely a continuous random variable. The task of making predictions based on these variables is a part of regression analysis, commonly studied in statistics - a branch of mathematics. The inquiries presented here are about establishing relationships between different sets of data and fall under the scope of probability and statistics, a subject typically covered in college-level courses. These problems involve calculating means (μ), interpreting probability density functions, and understanding discrete and continuous data distributions.