For a sample of 74 monthly observations the regression of the percentage return on gold (y) against the percentage change in the consumer price index (x) was estimated. The sample regression line, obtained through least squares, was as follows:
y = -0.003 + 1.11x
The estimated standard deviation of the slope of the population regression line was 2.31. Test the null hypothesis that the slope of the population regression line is 0 against the alternative that the slope is positive.