If the slopes of the line of regression of Y and X and of X and Y are `30^(@) and 60^(@)` respectively, then r(X, Y) is :

The slope of the line of regression of y on x is called the ______

If the lines of regreasion of y on x and x on y makes angle 30 ^(@) and 60^(@) respectively with positive direction of x - axis the correlation coefficient between x on y is

Slope of the line y=x is………….

Slope of the line x=2y is…………

b_(yx) is the ….. of regression line of y on x

The two towers of heights x and y, standing on level ground, subtend angles of 30^(@) and 60^(@) respectively at the centre of the line joining their feet. Then, find x: y