[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 66 + 59", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "125"}, {"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: 12 × 5", "difficulty": "medium", "explanation": "Multiply: 12×5=60", "needs_review": false, "correct_answer": "60"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 4", "difficulty": "medium", "explanation": "Multiply: 16×4=64", "needs_review": false, "correct_answer": "64"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 5", "difficulty": "medium", "explanation": "Multiply: 2×5=10", "needs_review": false, "correct_answer": "10"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 13", "difficulty": "medium", "explanation": "Multiply: 7×13=91", "needs_review": false, "correct_answer": "91"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 2", "difficulty": "medium", "explanation": "Multiply: 6×2=12", "needs_review": false, "correct_answer": "12"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 8", "difficulty": "medium", "explanation": "Multiply: 15×8=120", "needs_review": false, "correct_answer": "120"}]