Question

N=-D(n2-n1)/(x2-x1) D is diffastion.What are the dimensions of D.

Answer 1

We don't have much to go on.

The dimensions of D depend on the dimensions of N, n, and x, and we don't know what any of those stand for.

It might help if we had ever heard of 'diffastion', but we're striking out there too.