CREATE TABLE table_name_66 (number INT, opponent VARCHAR, time VARCHAR)

What number has the opponent Fokker d.vii with a time of 600?
SELECT SUM(number) FROM table_name_66 WHERE opponent = "fokker d.vii" AND time = 600
SELECT SUM("number") FROM "table_name_66" WHERE "fokker d.vii" = "opponent" AND "time" = 600