All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.
(i)
(a)
(b)
(iii) Since the product moment correlation coefficient is close to 1 for (ib), the model is the better model.
(iv) From GC, the regression line of F on is
(3SF)
When
Since is the independent or controlled variable, neither the regression line of nor the regression line of should be used.