# 5 A prisoner of war camp consists of 20 prison cells arranged in 4 rows and 5 columns. The daily cost of keeping a prisoner in each cell is shown in the table below. Only one prisoner may be kept per cell. Suppose that 9 prisoners are taken during a battle, 8 of which are normal prisoners and one is a really “bad guy.” The bad guy is so bad that it is not safe to keep a prisoner in any cell adjacent to his. For instance, if the bad guy is in row 3, column 4, denoted (3, 4), then no prisoner may be kept in (3, 3), (2, 4), (3, 5) or (4, 4). Cells that share a corner with his, such as (2, 5)

5 A prisoner of war camp consists of 20 prison cells arranged in 4 rows and 5 columns. The daily cost of keeping a prisoner in each cell is shown in the table below. Only one prisoner may be kept per cell.

Suppose that 9 prisoners are taken during a battle, 8 of which are normal prisoners and one is a really “bad guy.” The bad guy is so bad that it is not safe to keep a prisoner in any cell adjacent to his. For instance, if the bad guy is in row 3, column 4, denoted (3, 4), then no prisoner may be kept in (3, 3), (2, 4), (3, 5) or (4, 4). Cells that share a corner with his, such as (2, 5)