A summary of total charges from a small cafs natural gas bills is provided below:

Month	kJ	Cost
October	17	$186
November	16	187
December	28	235
January	36	265
February	32	280
March	17	207

Using regression analysis, the cost rate for the variable cost component is:

a.

$4.31/Kj

b.

$2.25/Kj

c.

$5.80/Kj

d.

$19.01/Kj