Morrisey & Brown, Ltd., of Sydney is a merchandising company that is the sole distributor of a product that is increasing in popularity among Australian consumers. The company's income statements for the three most recent months follow:

Morrisey & Brown, Ltd. Income Statements For the Three Months Ended September 30
	July		August		September
Sales in units	1,800		3,400		5,100
Sales revenue	A$ 309,600		A$ 584,800		A$ 877,200
Cost of goods sold	133,200		251,600		377,400
Gross margin	176,400		333,200		499,800
Selling and administrative expenses:
Advertising expense	70,200		70,200		70,200
Shipping expense	43,000		63,800		85,900
Salaries and commissions	103,100		163,900		228,500
Insurance expense	8,600		8,600		8,600
Depreciation expense	41,700		41,700		41,700
Total selling and administrative expenses	266,600		348,200		434,900
Net operating income (loss)	A$ (90,200	)	A$ (15,000	)	A$ 64,900

(Note: Morrisey & Brown, Ltd.'s Australian-formatted income statement has been recast in the format common in the United States. The Australian dollar is denoted here by A$.)

Requirement 2:
(a)	Using the high-low method, separate each mixed expense into variable and fixed elements. (Omit the "A$" sign in your response.)

Variable cost	A$	per unit	A$	per unit
Fixed cost	A$		A$

(b)	State the cost formula for each mixed expense. (X represents sales in units). (Omit the "A$" sign in your response.)

	Y = A$	+	A$	X
	Y = A$	+	A$	X