First of all, the solutions to our three exercises of part 2:
Exercise 1: White to move will win, Black to move doesn't change a thing!
Exercise 2: Black can draw if it is his turn to move
Excercise 3: Black to move wins but only with one correct move!
And now to our new problems and studies of today, we are getting (a little bit) more complicated.
Problem 1: White can win but there is only one move to achieve this
I find it extremely interesting that there is indeed only one move that will win for White. Experienced players may see it at first sight, I am not sure and it would be interesting to hear their opinions, do they immediately see what needs to be done or is some longer thinking necessary?
Okay, here is the answer:
Only 1.Kd4! is winning.
Let us play through some variants on the following board
Now, two little easier positions that we should keep in mind
Problem 2: White to move, can he win?
Problem 3:Black to move