CREATE TABLE table_39415 ("Call sign" TEXT, "Frequency MHz" FLOAT, "City of license" TEXT, "ERP W" FLOAT, "Class" TEXT, "FCC info" TEXT)

What is the ERP W for K236AM?
SELECT "ERP W" FROM table_39415 WHERE "Call sign" = 'k236am'
SELECT "ERP W" FROM "table_39415" WHERE "Call sign" = 'k236am'