1.) Yolk
2.) First trip, move 1 orc, 1 hobbit on the boat and to the other side. 2nd trip, 2nd trip, move 1 orc and 1 hobbit to the other side. 3rd trip move the remaining orc and hobbit over to the other side. viola!
3.) Yes, he absolutely has to pass one same point at the exact same time. He has to go the same distance in the same time. If there is 1 hour left and he has gone half way, he has to make up for it somehow and at one point he will cross the same spot at the same spot.
4.) 5010? I hope that's right.
5.) C
6.) False