• Are enclosed list of numbers and/or letters done in Nemeth mode? For example,(1, 2, 3) or A(1.5, 0) (grid coordinates).
I would do coordinate grids in Nemeth (as enclosed lists).
• Are compound expressions done in Nemeth mode? For example “45-ohm” or “carbon-14”. I noticed in the NBA Publication Nemeth/UEB Example 11 page 14 Mrs. Worthington encapsulated “3.0-m” in Nemeth and I assumed it done so because it’s a compound expression.
It's done that way because it's used in a math context. If you had carbon-14 and it's not used in any equations in the text surrounding it, you can do it in UEB.
• Could you please clarify the Provisional Guidance Additional Guidelines #2 concerning symbols such as the percent sign. If it’s something like “9% a year” and nowhere within that volume is the percent sign used in math notation, however it was used in pervious volumes and will be used in the future. Do we switch? do we stay in UEB? How important is the consistency of symbol usage?
This is a tougher one. You have to review the book you are doing. If percent signs are used consistently is math contexts (within equations, etc) you should do them all in Nemeth. But...if they aren't being used in equations or formulas, you can do them in UEB. Consistency is always important in braille, but I think using Nemeth and UEB together will change that to some degree...there will be itemized material that uses both Nemeth and UEB indicators...or number with decimals (like Section 3.2) done in UEB and in Nemeth (3.2+2.3). Do the best you can and try to keep things as consistent as possible. In this case, I would look at things in chunks. If you have a chapter on percents where most of the use of the % sign is mathematical, do them all in Nemeth...but if all the other chapters in the book use the % symbol rarely and in non-math context, it's ok to do those in UEB. Sorry I don't have a hard and fast rule for this!