For the first problem remember that, since George is travelling upstream, the speed of his boat is equal to the speed of the river plus the speed of his boat in still water.

For the second problem, the speed behaves similarly as in the first problem. When the pigeon travels in the same direction as the wind its speed is equal to the speed of the wind plus its real speed; and when it travels in the opposite direction of the wind its speed is equal to its real speed minus the speed of the wind.