[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 63 + 41", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "104"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Identity property", "Distributive property", "Commutative property", "Associative 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: 12 × 2", "difficulty": "medium", "explanation": "Multiply: 12×2=24", "needs_review": false, "correct_answer": "24"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 6", "difficulty": "medium", "explanation": "Multiply: 16×6=96", "needs_review": false, "correct_answer": "96"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 15", "difficulty": "medium", "explanation": "Multiply: 7×15=105", "needs_review": false, "correct_answer": "105"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 10", "difficulty": "medium", "explanation": "Multiply: 6×10=60", "needs_review": false, "correct_answer": "60"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 10", "difficulty": "medium", "explanation": "Multiply: 5×10=50", "needs_review": false, "correct_answer": "50"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 2", "difficulty": "medium", "explanation": "Multiply: 10×2=20", "needs_review": false, "correct_answer": "20"}]