OK. Lets assume a fighter with a 10 BAB. No str/dex or any other modifiers other than those feats you described.Takes his full round attack.
Takes his first shot at +8 since rapid shot decreases the hit by 2. This first shot is actually 2 arrows in 1. If the attack hits, both arrows hit. (This is the manyshot shot which would be his normal first attack)
Takes his second shot at a +3. (This is his normally second shot)
Takes his 3rd shot at ??? not sure if it is at +8 or +3 or -2. (This is the extra shot from rapid shot)
ncG1vNJzZmivp6x7prrWqKmlnF6kv6h706GpnpmUqHyzrc%2Bim2armKTBbrnAp7CsoJ%2Bpe3OFlnFtcmc%3D