Weston Corporation is considering eliminating a department that has a contribution margin of $70,000 and $140,000 in fixed costs. Of the fixed costs, $100,000 cannot be avoided. The effect of eliminating this department on Weston's overall net operating income would be:

	an increase of $70,000.
	a decrease of $70,000.
	an increase of $30,000.
	a decrease of $30,000.