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The length of a species of fish is to be represented as afunction of the age (measured in days) and water temperature(degrees Celsius). The fish are kept in tanks at 25, 27, 29 and 31degrees Celsius. After birth, a test specimen is chosen at randomevery 14 days and its length measured.

	Age	Temp	Length
1	14	25	620
2	28	25	1,315
3	41	25	2,120
4	55	25	2,600
5	69	25	3,110
6	83	25	3,535
7	97	25	3,935
8	111	25	4,465
9	125	25	4,530
10	139	25	4,570
11	153	25	4,600
12	14	27	625
13	28	27	1,215
14	41	27	2,110
15	55	27	2,805
16	69	27	3,255
17	83	27	4,015
18	97	27	4,315
19	111	27	4,495
20	125	27	4,535
21	139	27	4,600
22	153	27	4,600
23	14	29	590
24	28	29	1,305
25	41	29	2,140
26	55	29	2,890
27	69	29	3,920
28	83	29	3,920
29	97	29	4,515
30	111	29	4,520
31	125	29	4,525
32	139	29	4,565
33	153	29	4,566
34	14	31	590
35	28	31	1,205
36	41	31	1,915
37	55	31	2,140
38	69	31	2,710
39	83	31	3,020
40	97	31	3,030
41	111	31	3,040
42	125	31	3,180
43	139	31	3,257
44	153	31	3,214

A. Is there evidence of collinearity between theindependent variables? Yes, temperature and length are collinear in that theircorrelation is quite high Yes, temperature and age of fish are collinear No, temperature and age have no correlation No, temperature and length have a low correlation Yes, Age and length have a high correlation None of the above B. What proportion of the variation in the responsevariable is explained by the regression? About 90 percent About 81 percent About 85 percent None of the above C. The F statistic indicates that: The regression, as a whole, is statistically significant More than half of the variation in Y is explained by theregression Age of fish is an important explanatory variable in themodel Length of fish is an important explanatory variable in themodel Water temperature is an important explanatory variable in themodel None of the above D. The t-test of significance indicatesthat: The regression, as a whole, is statistically significant More than half of the variation in Y is explained by theregression Age of fish contributes information in the prediction of lengthof fish Length of fish contributes information in the prediction of ageof fish Length of fish contributes information in the prediction oftemperature E. The t-test of significance indicatesthat (same question but choose the correct answer): The regression, as a whole, is statistically significant More than half of the variation in Y is explained by theregression Length of fish is an important explanatory variable in themodel Water temperature is an important explanatory variable in themodel None of the above F. Assuming you ran the regression correctly, plot theresiduals (against Y-hat). The plot shows that: The residuals appear to curve downwards, like a bowl facingdown The residuals appear to curve upwards, like a bowl facing up (Vshape) The residuals appear to be fanning out and are mostly spread outat the end The residuals appear random None of the above G. REGRESSION. Which of the following types oftransformation may be appropriate given the shape of the residualplot? Logarithmic transformation in both Y and the X variables Quadratic transformation to correct for curvilinearrelationship No transformation is necessary G. REGRESSION. This type of dataset is best described as a ____and a residual problem common with this type of data is ___ Cross-sectional data; heteroscedasticity Time series data; heteroscedasticity Cross-sectional data; residual correlation Time series data; residual correlation Cross-sectional data; multicollinearity None of the above