I think I have all IPs covered here. You can copy and paste this to each router under tclsh and off you go. Internetwork Expert’s solution guide has the full script if you want to type it up and run it each time from the process name.

foreach i {
150.1.1.1
150.1.2.2
150.1.3.3
150.1.4.4
150.1.5.5
150.1.6.6
150.1.7.7
150.1.8.8
150.1.10.10
183.1.0.3
183.1.0.4
183.1.0.5
183.1.123.1
183.1.123.2
183.1.123.3
183.1.17.1
183.1.17.7
183.1.28.2
183.1.45.4
183.1.45.5
183.1.46.6
183.1.105.5
183.1.105.10
183.1.6.6
183.1.107.7
183.1.107.10
54.1.1.6
192.10.1.10
} {ping $i}