It's not really relevant to the problem.
The relevance is that it's a really weird way to set up a problem. If P(H)=1 and P(H|A)=0.4 then it is necessarily the case that P(A)=0. If that's not immediately obvious to you, you may want to come back to this topic after sleeping on it.
Fair enough.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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