I'm going to answer this one as well as I feel like this is more formats than Nemeth. 🙂
I have seen this done a couple of other times. I have a couple of suggestions. First, I would not treat the answer boxes as Nemeth rectangles. They are not mathematical in nature, they are just answer blanks. Although there is no rule against using Nemeth rectangles...that's my opinion. For the answer boxes that have drop down choices: The way I've seen this done that I liked the best was to number the answer blanks (1 _ , 2 _, 3 _ and 4 _ [numbers and underscores in UEB] in this case) and then follow the question with a list of the answer choices. Of course, you would need a TN to explain the change to format (on the TN page as this happens throughout. If you don't have a TN page, put it before the first question of each worksheet set.
1.
less than 2.5%
between 2.5% and 16%
etc
2.
not possible
reasonable
Hope this helps!
Cindi