CREATE TABLE table_18475946_2 (rnag__mhz_ VARCHAR, transmitter VARCHAR)

What is the rnag for kippure transmitter?
SELECT rnag__mhz_ FROM table_18475946_2 WHERE transmitter = "Kippure"
SELECT "rnag__mhz_" FROM "table_18475946_2" WHERE "Kippure" = "transmitter"