[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 70 + 32", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "102"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Distributive property", "Identity 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: 17 × 2", "difficulty": "medium", "explanation": "Multiply: 17×2=34", "needs_review": false, "correct_answer": "34"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 18", "difficulty": "medium", "explanation": "Multiply: 19×18=342", "needs_review": false, "correct_answer": "342"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 2", "difficulty": "medium", "explanation": "Multiply: 14×2=28", "needs_review": false, "correct_answer": "28"}]