Riverton Corp., which began business at the start of the current year, had the following data:

Planned and actual production: $40,000$ units

Sales: $36,000$ units at $$25$ per unit

Production costs:

Variable: $$5$ per unit

Fixed: $$240,000$

Selling and administrative costs:

Variable: $$3$ per unit

Fixed: $$45,000$

a$.$ The gross margin that the company would disclose on an absorption$-$costing income statement is:

b$.$ The contribution margin that the company would disclose on a variable$-$costing income statement is: