91Ó°ÊÓ

The regression line is:

$\stackrel{Áåœ}{y}=6.4+0.93x$

The formula used:$b=r(\frac{s_y}{s_x})$

The slope and correlation coefficient have the following relationship:

$b=r(\frac{s_y}{s_x})$

The slope of the least-squares line is b, the sample correlation coefficient is $r$and the sample standard deviations for the variables $X$and $Y$are $s_x$and $s_y$respectively.

The ratio $\frac{s_y}{s_x}$is always positive since the standard deviation of any random variable cannot be negative. As a result, the sample correlation coefficient is proportional to the slope of the least-squares line. The sign of the slope and correlation coefficient will always be the same.

The slope of the least square line is positive in this case. As a result, the correlation will be positive, i.e. greater than $0$

Hence, the correct option is (a).