not sure cus i never paid attention since i find all SA's crap for archer :D
dmg up i believe adds flat + w/e number is to your pattack
long blow adds +100? range on normal hits could be that its even less
but 100 range is nothing and its for sure not going to make u win
focus will help u far more in cases like olympiad if u do it atleast cus u wont ding 500 crit rate there so better have dmg up > focus if u wanna do 2 sa's