Figure shows a table. The first column lists the six prefix lengths from /25 to /30. The second column lists the six subnet masks from 255.255.255.128 to 255.255.255.252. The third column shows the subnet mask in binary with the letter “n” above one bits and the letter “h” above zero bits. The effect is to show the borrowing of bits into the fourth octet from borrowing one bit in the first row (/25) to borrowing six bits in the last row (/30). The fourth and fifth columns show the number of subnets and hosts respectively. For example, borrowing 3 bits gets you 8 subnets with 30 hosts per subnet.