Penny Chairs has two plants that manufacture and ship chair parts to other manufacturers. Penny Chairs sells and ships to four manufacturers. The cost of shipping one chair from a plant to a customer is given in the following table.

Plant$/$Customer

Mesquite Furniture

Tonopah Fashions

Sumerlin Appliance

Charleston Furnishings

Bruderheim

$$1\mathrm{.}70$

$$2\mathrm{.}30$

$$2\mathrm{.}50$

$$2\mathrm{.}15$

Cardston

$$1\mathrm{.}95$

$$2\mathrm{.}35$

$$1\mathrm{.}65$

$$2\mathrm{.}95$

Exact Customer demand$/$week $($cases$)$

$1200$

$2000$

$2500$

$1400$

The plant in Bruderheim has a capacity of $3500$ cases per week, and the Cardston plant can produce $4000$ cases per week.

A$.$ Derive the minimum cost shipping plan.

B$.$ Tonopah Fashions is experiencing some financial problems. If Tonopah were to reduce its order by $1000$ cases, how would the minimum cost shipping plan change?