1. EASY

\(9 - 0 = \)

 
2. EASY

\(4 - 3 = \)

 
3. EASY

\(0 - 0 = \)

 
4. MEDIUM

\(9 - 4 = \)

 
5. MEDIUM

\(8 - 2 = \)

 
6. MEDIUM

\(8 - 1 = \)

 
7. MEDIUM

\(4 - 4 = \)

 
8. MEDIUM

\(7 - 3 = \)

 
9. HARD

\(50 - 30 =\)

 
10. HARD

\(9 - 6 - 1 =\)