say something thoughtful substantive about "In my personal life, I can examine how my exercise habits impact my overall mood. Let's say I track the number of days per week I exercise (variable X) and measure my mood on a scale of 1 to 10 (variable Y), where higher values indicate a better mood. Conducting a regression analysis on this data could provide insights into how exercise frequency affects my mood. After collecting data over several weeks, I perform a regression analysis and find the following results: Regression equation: Y = aX + b Where: Y = mood X = number of days per week exercising a = coefficient indicating the effect of exercise on mood b = intercept term Assuming I obtain the following regression equation: Y = 0.75X + 4.5 Coefficient of determination (R-squared): 0.65 The coefficient of determination (R-squared) tells us the proportion of the variance in the dependent variable (mood) that is predictable from the independent variable (exercise frequency). In this case, R-squared = 0.65 indicates that approximately 65% of the variance in mood can be explained by the number of days per week I exercise. To test the significance of the regression coefficient (a)