5. An agricultural researcher collected data, in appropriate units, on the annual rainfall \(x\) and the annual yield of wheat \(y\) at 8 randomly selected places. The data were coded using \(s = x - 6\) and \(t = y - 20\) and the following summations were obtained. $$\Sigma s = 48.5 , \quad \Sigma t = 65.0 , \quad \Sigma s ^ { 2 } = 402.11 , \quad \Sigma t ^ { 2 } = 701.80 , \quad \Sigma s t = 523.23$$

1. Find the equation of the regression line of \(t\) on \(s\) in the form \(t = p + q s\).
2. Find the equation of the regression line of \(y\) on \(x\) in the form \(y = a + b x\), giving \(a\) and \(b\) to 3 decimal places. The value of the product moment correlation coefficient between \(s\) and \(t\) is 0.943 , to 3 decimal places.
3. Write down the value of the product moment correlation coefficient between \(x\) and \(y\). Give a justification for your answer.