Table: radio_stations_4
Columns: call_sign
frequency_mhz
city_of_license
erp_w
class
fcc_info

Question: Name the call sign with frequency of 89.5
SQL: SELECT "call_sign" FROM radio_stations_4 WHERE "frequency_mhz" = 89.5

Question: Name the sum of frequency will call sign of k259aw
SQL: SELECT SUM("frequency_mhz") FROM radio_stations_4 WHERE "call_sign" = 'k259aw'