A study collected data on 15 15 randomly selected technology firms, recording each firm's research and development spending (in millions of dollars, explanatory variable x x ) and their annual profit growth rate (in percentage, response variable y y ) for the whole previous year. The least-squares regression line was computed and the residuals are assumed to be normally distributed. A hypothesis test at α = 0.05 \alpha = 0.05 for the slope gave a p p -value of 0.021 0.021 , and the 95 % 95\% confidence interval for the true slope β 1 \beta_1 is ( 0.08 , 0.64 ) (0.08, 0.64) . Based on these results, should the regression line be used to predict profit growth based on R&D spending? Why?

Yes, because the hypothesis test and confidence interval both indicate a significant positive relationship

No, because the regression line is not significant

No, because the p p -value is greater than 0.05 0.05

No, because the confidence interval contains zero

A study collected data on 1515 randomly selected technology firms...

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