In the next production period, the company has

$6$

$7$

$,$

$0$

$0$

$0$

$$square inches of board,

$1$

$0$

$1$

$,$

$0$

$0$

$0$

$$resistors$,$

$3$

$1$

$,$

$0$

$0$

$0$

$$memory cards, and

$3$

$,$

$7$

$2$

$5$

$$hours of assembly labor time available. The marketing department suggests that the production of each model does not exceed the expected demand.

Other important information is as follows. Models A and B are substitute goods, so that the demand for these two models, in combination, will not exceed

$2$

$,$

$0$

$0$

$0$

$$units

$($

although the sum of each model's demand is

$2$

$,$

$8$

$0$

$0$

$)$

$.$

$$You must ensure that this condition holds in your production schedule.

The company's objective is to maximize its revenue by finding the optimal number of production units for each model. Your task is to help the company management make the optimal production decision. The numbers of production units should be integral numbers. Use the integer tolerance of

$0$

$($

zero

$)$

$$when solving the problem.