Given the following information set up the problem in a transportation table and solve for the minimum$-$cost plan. Solve by modifying textbook Table $11\mathrm{.}6.$

PERIOD

$123$

Demand $550700750$

Capacity

Regular $500500500$

Overtime $505050$

Subcontract $120120100$

Beginning inventory $100$

Costs

Regular time $ $60$ per unit

Overtime $ $80$ per unit

Subcontract $ $90$ per unit

Inventory carrying cost $ $1$ per unit per month

Back$-$order cost $ $3$ per unit per month

Suppose that regular$-$time capacity will be reduced to $440$ units in period $3$ to accommodate a companywide safety inspection of equipment. What will the additional cost of the optimal plan be$?$