3. Suppose you have designed a help system based on Example 10.5 and much of the underlying system which the help pages are about has changed. You are now very unsure about which help pages will be requested, but you may have a good model of which words will be used given the help page. How can the help system be changed to take this into account? [Hint: You may need different counts for P(hi) and P(wj ∣ hi).]