simple rules question (manyshot)

[Thac0 Redeye]

If I had an archer chara that has a single ranged attack (after all the bonuses, and standard arrow) is +10. If I shot a +2 arrow and a standard arrow with a non magical bow with many shot what is my attack roll?
Thanks

[Khedrac]

I think you would roll the D20 for the attack roll once, but calculate the result differently for the different arrows.