re:
Now that I'm home, I followed the very clear instructions to wipe the cache partition. Alas, that didn't seem to make any difference that I could see. Chrome was still not listed among the programs that could open an .html file that I have on my tablet. (The file is a list of links to sites that I use a lot. I've used a similar file as the start page on my Windows computers for many years.) The Nexus tablet seems to recognize that the file is an html file that should be opened with a browser, so it lists the two other browsers I have installed on my tablet (Dolphin and Pale Moon), but even after clearing the cache partition, the list of available programs hasn't changed.
I might add that I'd not only like to add Chrome but also remove programs I would NOT want to use, which include ES Note Editor (I'm not even sure I have this on my tablet), HTML Viewer (I didn't put this on the tablet, but perhaps it came built in?), Moon+ Reader Pro (which I added for reading pdfs and some other kinds of files, but not html files), WPS Office (great for all kinds of files, but I'd not want to use it for html files), and TextMaker Mobile (a useful program for some kinds of text files, but not for html files). Why the Nexus includes these but not Chrome remains a mystery.
I should add that I've also tried an app called Better Open With, but it too did not include Chrome among the possible browsers that would open my .html file, so I uninstalled the app. I'm not sure what else I could try. On Windows, there are programs one can add that will substitute a longer text string when one types a shorter one: typing TY, for example, might replace TY with Thank You. But I don't know of any such program for Android. If there were such a program, I might be able to click on Chrome only when I wanted to go to the one site that Chrome seems to handle better than my other browsers. But to do that now, I'd have to type in the URL each time. Not the end of the world, but a PITA.