- Problem 73,
- Problem 170,
- Problem 169,
- Problem 286,
- Problem 285,
- Problem 284,
- Problem 283,
- Problem 282,
- Problem 281,
- Problem 280,
- Problem 279,
- Problem 168,
- Problem 167,
- Problem 166,
- Problem 165,
- Problem 278,
- Problem 277,
- Problem 276,
- Problem 275,
- Problem 72,
- Problem 164,
- Problem 163,
- Problem 162,
- Problem 161,
- Problem 274,
- Problem 273,
- Problem 272,
- problem 271,
- problem 71,