After reading the example questions, from the prior attempt [Edit: presuming those are the ones shown now], I have a number of ideas:
1) For each example question, preface the question with an explanation why would the question be asked?
If an explanation prefaced the question it would help demonstrate question context and relevance. Some questions seemed too obscure to be of community interest or be likely to have any/many members capable of answering it; a couple were too easy.
2) One should be mindful that "Railroad" and "Railway", as well as everything concerning the two terms (ie. guage, equipment, operation, and etc.), will vary by country and time period. This could cause some confusion/misunderstandings.
3) What's true about #2 above holds for modelling, to some extent, unless one is mindful that, for simple example, "HO" could mean "HOn3-1/2", "H0m", "HOn3", "HOe", and etc. depending on country.