[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 32 + 21", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "53"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Identity property", "Distributive property", "Associative property", "Commutative 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 × 3", "difficulty": "medium", "explanation": "Multiply: 12×3=36", "needs_review": false, "correct_answer": "36"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 7", "difficulty": "medium", "explanation": "Multiply: 4×7=28", "needs_review": false, "correct_answer": "28"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 10", "difficulty": "medium", "explanation": "Multiply: 10×10=100", "needs_review": false, "correct_answer": "100"}]