Given the following cost and activity observations for Smithson Company's utilities, use the high-low method to calculate Smithson's fixed costs per month.

	Cost	Machine Hours
January	$82,980	9,700
February	145,880	18,200
March	101,080	12,100
April	120,200	14,700

a.$9,000

b.$19,000

c.$35,800

d.$11,200