Mrs$.$ Smith Corporation is preparing an aggregate production plan for washing machines for the next four quarters. The company's expected quarterly demand is given in the following chart. The company will have $1,000$ washers in inventory at the beginning of the year and wishes to maintain at least that number at the end of each quarter.

Quarter

Demand

$1$

$4,000$

$2$

$6,000$

$3$

$3,000$

$4$

$7,000$

Total

$20,000$

Given the above table of forecasted demand, if Mrs$.$ Smith Corporation prefers a level plan, what should be the regular production rate per quarter?

Question $4$ options:

Regular production will vary each month

$6000$

$5000$

$4000$