All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.
(i)
(a)
![Rendered by QuickLaTeX.com r = 0.9860](https://theculture.sg/wp-content/ql-cache/quicklatex.com-89412c8fb8d43c27f5a39a9f5ed1f266_l3.png)
(b)
![Rendered by QuickLaTeX.com r = 0.9907](https://theculture.sg/wp-content/ql-cache/quicklatex.com-f40241eca4e53ed0bdf3c044066d31cd_l3.png)
(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.