Use Notepad to create a csv file:
1. Open Notepad, type °C (Alt 248 then C). Then save as test.csv with UTF8
encoding. In hex, it should read (ef bb bf c2 b0 43), where "ef bb bf" is
BOM, "c2 b0" is the degree sign and "43" is C.
2. Double click this file, Excel opens it up. It shows °C in the first
cell. Why? Why noy simply °C?
3. If I use the Open dialog to open the file, the "Text Import Wizard"
shows up, showing the encoding correctly. Click finish, °C is shown in the
first cell.
4. If I create the file using Unicode encoding from Notepad, both methods
show °C.

I would like to keep UTF8 encoding (to keep the file smaller). How can I
make Excel to display °C in case 2?

Thank you.