The following are the Wyeth Company's unit costs of making and selling an item at a volume of $10,000$ units per month, which represents the company's capacity:

Manufacturing:

Direct Materials $$1\mathrm{.}00$

Direct Labour $$2\mathrm{.}00$

Variable Overhead $$0\mathrm{.}50$

Fixed Overhead $$0\mathrm{.}90$

Selling and Administrative:

Variable $$1\mathrm{.}50$

Fixed $$0\mathrm{.}60$

Present sales amount to $9,000$ units per month. An order has been received from a customer in a foreign market for $1,000$ units. The order would not affect current sales. Fixed costs, both manufacturing and selling and administrative, are constant within the relevant range between $8,000$ and $10,000$ units per month. The variable selling and administrative costs would have to be incurred for this special order as well as all other sales. Assume direct labour is a variable cost.

How much will the company's operating income be increased or $($decreased$)$ if it prices the $1000$ units in the special order at $$6$ each

Multiple Choice

A$($$$500)$

B$$400$

C$$1,000$

D$$2,500$