Jóhannes plans to examine the salary of a middle manager in a large company. He collects data on salaries and how long they have been employed as middle managers with the aim of creating a model that...

Extracted text: Jóhannes plans to examine the salary of a middle manager in a large company. He collects data on salaries and how long they have been employed as middle managers with the aim of creating a model that can predict salaries with work experience. Jóhannes has a total of data from 20 randomly selected middle managers who range from being new to the job to having 12 years of work experience. Jóhannes started by drawing the data and sees that the relationship is linear. He also calculates some light quantities that can be seen below: Change Average Standard Deviation Wages Work Experience He also calculated the correlation coefficient between wages and work experience and obtained r = 0.82. standard deviation Change salary average 761041 238473 work experience 5.65 3.71 a. Find an equal regression line for John's model. b. What is the explanatory power of the model and what does it tell us? c. How much does a middle manager's salary increase in five years according to the model? d. Use the model to predict the salary of a middle manager with 20 years of work experience. Is the forecast reliable? Justify.