The following information is taken from Blood Work Testing Service:

Month	Number of Tests Performed	Total Cost of Testing
January	110	$5,500
February	90	$4,500
March	80	$4,400
April	100	$5,000
May	130	$6,000
June	120	$5,600
July	70	$4,000
August	60	$3,200
September	50	$3,400
October	40	$2,400

Required: Using the high-low method, determine the following:

a. The variable cost per test.

b. The total fixed cost of operating the testing facility.

c. The expected cost for a month if 140 tests are performed