$13.xy.$

$\backslash$table$[[x$:$5,3,7,9,2,4,6,8],[y$:$20,000,23,000,15,000,11,000,27,000,21,000,17,000,14,000]]$

$(1)xy($covariance$).$

$(2)xy($coefficient of correlation$).$

$(3)y=a+bx,ab.$

$14.xyy=a+bxab.$

$\backslash$table$[[$X: $12,13,15,17,20,21,25],[Y$:$300,400,350,500,550,600,580]]$