user: Question: What is the ERP W number where the frequency is smaller than 91.1?
Columns: ['Call sign', 'Frequency MHz', 'City of license', 'ERP W', 'Class', 'FCC info']
Types: ['text', 'real', 'text', 'real', 'text', 'text']
Sample row: ['W238AW', 95.5, 'West View, South Carolina', 55.0, 'D', 'FCC']
SQL:

assistant: SELECT "ERP W" FROM "Table" WHERE "Frequency MHz" < 91.1;