You can. It's really not needee though.
3600w/220v is 16.36. Your a lil bit over 50% load. Just run the 10/2, you'll never need the 8/2, it's a waste of money. Doesn't matter if u put the largest wire u can, the breaker will still only allow "30 amps"
there is 2 hots and a ground in the box. It...