Susan's Handbags typically sells $1,000$ handbags each month with a unit selling price of $$65.$ Susan's variable costs are $$35$ a unit, and the fixed costs are $$25,000$ per month. Susan wishes to raise the unit selling price to $$75$ while maintaining her current cost structure. If she implements the price change, only $850$ units will be sold per month. If Susan changes the price and the quantity falls, the contribution margin will

increase by $$4,000.$

remain unchanged.

decrease by $$5,000.$

increase by $$9,000.$