CREATE TABLE table_49240 ("Call sign" TEXT, "Frequency MHz" FLOAT, "City of license" TEXT, "ERP W" FLOAT, "Class" TEXT, "FCC info" TEXT)

Which Frequency MHz has a Call sign of k210dv?
SELECT MAX("Frequency MHz") FROM table_49240 WHERE "Call sign" = 'k210dv'
SELECT MAX("Frequency MHz") FROM "table_49240" WHERE "Call sign" = 'k210dv'