Question: When the network mask is 255.255.255.252 what is the prefix size?
SQL: SELECT "Prefix size" FROM "1-149426-4" WHERE "Network mask" = '255.255.255.252';

Question: available subnets leading total is?
SQL: SELECT MAX("Available subnets") FROM "1-149426-4";

Question: When the network mask is  255.255.255.128 what is the lowest available subnet?
SQL: SELECT MIN("Available subnets") FROM "1-149426-4" WHERE "Network mask" = '255.255.255.128';

Question: When the network mask is 255.255.255.224 what is the highest  total usable host?
SQL: SELECT MAX("Total usable hosts") FROM "1-149426-4" WHERE "Network mask" = '255.255.255.224';