CREATE TABLE table_78667 ("City" TEXT, "1860" TEXT, "1870" TEXT, "1880" TEXT, "1890" FLOAT, "1900" FLOAT, "1910" FLOAT, "1920" FLOAT)

What is the 1880 figure when 1860 is N/A and 1910 is 494?
SELECT "1880" FROM table_78667 WHERE "1860" = 'n/a' AND "1910" = '494'
SELECT "1880" FROM "table_78667" WHERE "1860" = 'n/a' AND "1910" = '494'