[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 79 + 83", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "162"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Distributive property", "Commutative property", "Associative property", "Identity property"], "question": "Which property states a+0=a?", "difficulty": "easy", "explanation": "The identity property of addition states that adding 0 to any number gives that number.", "needs_review": false, "correct_answer": "Identity property"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 18", "difficulty": "medium", "explanation": "Multiply: 18×18=324", "needs_review": false, "correct_answer": "324"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 9", "difficulty": "medium", "explanation": "Multiply: 9×9=81", "needs_review": false, "correct_answer": "81"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 9", "difficulty": "medium", "explanation": "Multiply: 17×9=153", "needs_review": false, "correct_answer": "153"}]