Denver Office Equipment manufactures and sells metal shelving. It began operations on January$1,2020.$ Revenues in $2020$ were $ $404,800.$ The selling price per unit and the purchase price per pound of direct materials were stable throughout the year. The$$ company's ending inventory of finished goods is carried at the average unit manufacturing cost for $2020.$Finished$-$goods inventory at December$31,2020,$ was $ $28,320.$ Costs incurred for $2020$ are as follows$($V stands for$$ variable; F stands for$$ fixed$)$:

Direct materials used

$$142,000$ V

Direct manufacturing labor costs

$$27,000$ V

Plant energy costs

$$6,000$ V

Indirect manufacturing labor costs

$$15,000$ V

Indirect manufacturing labor costs

$$12,000$ F

Other indirect manufacturing costs

$$13,000$ V

Other indirect manufacturing costs

$$21,000$ F

Marketing, distribution, and customer$-$service costs

$$130,000$ V

Marketing, distribution, and customer$-$service costs

$$44,000$ F

Administrative costs

$$53,000$ F

Variable manufacturing costs are variable with respect to units produced. Variable$$ marketing, distribution, and$$ customer$-$service costs are variable with respect to units sold.Inventory data are as follows$$:

Beginning: January $1,2020$

Ending: December $31,2020$

Direct materials

$0$ lb

$2,100$ lbs

Work in process

$0$ units

$0$ units

Finished goods

$0$ units

$?$ units

Production in $2020$ was $100$ comma $000$ units. Two pounds of direct materials are used to make one unit of finished product. $1.$

Calculate direct materials$$ inventory, total$$ cost$,$ December$31,2020.$

$2.$

Calculate$$ finished$-$goods inventory, total$$ units, December$31,2020.$

$3.$

Calculate selling price in $2020.$

$4.$

Calculate operating income for $2020.$