l $.$ The following information in alphabetical order pertains to Alexander Company for March $2023$:

Beginning direct materials inventory $$30,000$

Beginning finished goods inventory $40,000$

Beginning work$-$in$-$process inventory $50,000$

Direct labor $200,000$

Direct materials purchases $170,000$

Ending direct materials inventory $35,000$

Ending finished goods inventory $42,000$

Ending work$-$in$-$process inventory $54,000$

Factory overhead $$ fixed $120,000$

Factory overhead $$ variable $90,000$

Sales $800,000$

Selling and administrative expenses $100,000$

Calculate the following, assuming there are no income taxes:

a$.$ Direct materials used

b$.$ Cost of goods manufactured

c$.$ Cost of goods sold

d$.$ Operating income

e$.$ Conversion costs

f$.$ Prime costs