8. Given: x-bar=18.86, y-bar=25.83, s,=8.38 s,=8.53 r=.984. Find the regression equation for this line. If the x variable increases by one unit, what happens to the y variable? What amount of the variance in the y variable is explained by its linear relationship with the x variable? What is the nature of the relationship between these two variables? Explain why. Describe the strength of the relationship. Explain your statement. 9. Dene bias. What are the principle tools for combating bias and variability in research