CREATE TABLE table_204_633 (id DECIMAL, "launch date" TEXT, "operator" TEXT, "name" TEXT, "sample origin" TEXT, "samples returned" TEXT, "recovery date" TEXT, "mission result" TEXT)

how many mission failures were there for the cosmos 305 ?
SELECT COUNT(*) FROM table_204_633 WHERE "name" = 'cosmos 305'
SELECT COUNT(*) FROM "table_204_633" WHERE "name" = 'cosmos 305'