[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 54 + 63", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "117"}, {"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: 2 × 6", "difficulty": "medium", "explanation": "Multiply: 2×6=12", "needs_review": false, "correct_answer": "12"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 4", "difficulty": "medium", "explanation": "Multiply: 4×4=16", "needs_review": false, "correct_answer": "16"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 6", "difficulty": "medium", "explanation": "Multiply: 12×6=72", "needs_review": false, "correct_answer": "72"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 14", "difficulty": "medium", "explanation": "Multiply: 2×14=28", "needs_review": false, "correct_answer": "28"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 14", "difficulty": "medium", "explanation": "Multiply: 17×14=238", "needs_review": false, "correct_answer": "238"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 9", "difficulty": "medium", "explanation": "Multiply: 8×9=72", "needs_review": false, "correct_answer": "72"}]