Going through the Navigator to do practice, you never have explanations for the hard questions. But you always do for the stupid easy ones. why? No one cares about an explanation for the easy ones - if someone is getting those wrong it is not very hard to figure out why.
For example, in the PS section of OG you provide an explanation for #131 - a silly read the bar graph and count problem - but none for 125, 134, or 137 which are legitimately hare problems.
Plus, by percent of students benefiting, providing explanations for the hardest ones is most helpful since the most people got it wrong by definition! What are you pulling here???
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