. The following selected data for March were taken from Rubenstein Company's financial statements:

	Cost of goods available for sale....................	P65,000
	Manufacturing overhead..............................	P20,000
	Cost of goods manufactured........................	P51,000
	Finished goods inventory, ending.................	P10,000
	Direct materials used..................................	P15,000
	Sales..........................................................	P105,000
	Selling and administrative expenses.............	P30,000
	Direct labor................................................	P20,000
	Work in process inventory, beginning...........	P0

1-A. The gross margin was ________

1-B. The beginning finished goods inventory was _______

1-C. The ending Work in process Inventory was _____