Help please!

I have two rows of numbers with some cell that will contain 'N/A".

If the top row is highest I need it highlighted yellow if it is not highest
or is "N/A" the cell needs to remain with no fill.

I can do a condtional formatting that works great until a cell contains the
"N/A". Is there a formula that I can do in conditional formatting or some
other options that will solve this problem.