user: Question: What is the start address when the network number bit field is 16?
Columns: ['Class', 'Leading bits', 'Size of network number bit field', 'Size of rest bit field', 'Number of networks', 'Addresses per network', 'Start address', 'End address']
Types: ['text', 'real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Class A', 0.0, '8', '24', '128 (2 7 )', '16,777,216 (2 24 )', '0.0.0.0', '127.255.255.255']
SQL:

assistant: SELECT "Start address" FROM "Table" WHERE "Size of network number bit field" = '16';