How to: Subscript characters in cell.
Solution:
Select 'Cells...' from the 'Format' menu and select the 'Subscript' check box in the 'Effects' group.
1) Select the characters to be subscripted.
2) Select the 'Format' menu and select 'Cells...'. (The Format Cells dialog box appears.)
NOTE: When characters or numbers are selected in a cell, only the 'Font' tab appears in the 'Format Cells' dialog box.
3) Select the 'Subscript' check box in the 'Effects' group.
the Subscript check box
4) Click 'OK'.
NOTE: Multiple character formatting works ONLY for TEXT. Precede values with a single quotation mark (') or by formatting the cell as text before entering the values.