CREATE TABLE table_70783 ("Lithium" TEXT, "Sodium" TEXT, "Potassium" TEXT, "Rubidium" TEXT, "Caesium" TEXT)

what is the type of lithium when rubidium is nabr (1.9)?
SELECT "Lithium" FROM table_70783 WHERE "Rubidium" = 'nabr (1.9)'
SELECT "Lithium" FROM "table_70783" WHERE "Rubidium" = 'nabr (1.9)'