Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What number has the opponent Fokker d.vii with a time of 600?

### Inputs:
table_name: table, columns: ['Number', 'Time', 'Aircraft', 'Opponent', 'Location']

### Response:
SELECT SUM Number FROM table WHERE Opponent = fokker d.vii AND Time = 600