I have $2$ parts. Please answer with expolanations and calculations properly:

Q$2($a$)$: The Alpine House, Inc, is a large retailer of snow skis.

The company assembled the information shown below for the quarter ended June $30.$

Sales $250000$

Selling price per pair of skis $1000$

Variable selling expense per pair of skis $100$

Variable administrative expense per pair of skis $50$

Total fixed selling expense $30000$

Total Fixed administrative expense $15000$

Beginning merchandise inventory $25000$

Ending Merchandise inventory $30000$

Merchandise purchases $110000$

What is the net operating income?

Options:

$35000$

$43750$

$62500$

$82300$

Q$2($b$)$:

The Alpine House, Inc, is a large retailer of snow skis.

The company assembled the information shown below for the quarter ended June $30.$

Sales $250000$

Selling price per pair of skis $1000$

Variable selling expense per pair of skis $100$

Variable administrative expense per pair of skis $50$

Total fixed selling expense $30000$

Total Fixed administrative expense $15000$

Beginning merchandise inventory $25000$

Ending Merchandise inventory $30000$

Merchandise purchases $110000$

What is the contribution margin?

Options:

$75000$

$88750$

$62500$

$107500$