6. A manufacturer of metal sheets produces rolls of standard fixed width w=1.5m and of standard length L=12m. A large order is placed by a customer who needs sheets of width w and varying lengths. In particular, bi sheets with length li and width w for i= 1,2,3,4,5 are ordered as follow. The manufacturer would like to cut the standard rolls in such a way as to satisfy the order and to minimize the waste. No of order li bi 1 2 100 3 250 3 4 70 4 5 320 5 7 95 2.