Question about a combinatorics problem

GRE Quant Problem Solving
1

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In the lecture, Greg says that if order matters, we use permutation, and if order doesn’t matter, we use combination.

In this example, doesn’t the order of the N and E choice matter? As in, a path that is NENENEE is not equal to NNNEEEE. So why are we using the combination formula and not the permutation?

2

Here, he is cancelling out the repeatation which we are allowed to do in the case of permutation.

3

We don’t cancel out anything in Permutation though?