user: ### NOW ANSWER:
Question: If the version is 1.5b, what is the distribution mechanism?
Columns: ['Version', 'Release date', 'Distribution mechanism', 'Features', 'Security issues']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1.5a', 'September 1997–March 1998', 'Microsoft website', 'Service release', '99-025']
SQL:

assistant: SELECT "Distribution mechanism" FROM "Table" WHERE "Version" = '1.5b';