[CST-2] Information thry & neural nets

[Tom Puverle]

There are two things I am not clear on, any help would be very appreciated:

1) In the learning guide on Neural Networks: Exercise 9
How do you get from the first equation to the second? (There's
one line between the two equations, starting "and similarly for P~(N|X)..."

2) Information thry, lecture notes, page 42.
He deduces that h(Y|X) = h(N) "since N is independent of X"... I don't
understand. Anyone point me in the right direction?

Thanks.