Related Clues:

• Part of 51-Across: Abbr.
• Si or No, e.g.
• Ca, Co or Cu
• Grades K-6
• Purchase from Pat?
• Periodic table entry (Abbr.)
• A or I, e.g.
• C or Al
• It's before middle sch.
• A or e, say
• I or O
• aeio or u
• Not a consonant
• For the letter one may be in debt to between 5 and 50
• 5 in red to 50 by letter