Cоnsider the fоllоwing model аnd its pаrаmeters and variables. Parameters: n = number of existing facilities. m = number of regional markets. Dj = Annual market size of regional market j. The demand of each market is positive. Ki =capacity of production facility i cij = cost of shipping from facility i to regional market j fi = Annual fixed cost of facility i Variables: xij = Number of units shipped from facility i to regional market j. zi = Binary variable indicating whether to shutdown facility i. zi =1 means to shutdown it, 0 otherwise. Model: Which of the following statements is not correct?