[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 65 + 64", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "129"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Associative property", "Commutative property", "Identity property", "Distributive 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 × 10", "difficulty": "medium", "explanation": "Multiply: 12×10=120", "needs_review": false, "correct_answer": "120"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 2", "difficulty": "medium", "explanation": "Multiply: 16×2=32", "needs_review": false, "correct_answer": "32"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 3", "difficulty": "medium", "explanation": "Multiply: 15×3=45", "needs_review": false, "correct_answer": "45"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 2", "difficulty": "medium", "explanation": "Multiply: 7×2=14", "needs_review": false, "correct_answer": "14"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 16", "difficulty": "medium", "explanation": "Multiply: 16×16=256", "needs_review": false, "correct_answer": "256"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 17", "difficulty": "medium", "explanation": "Multiply: 19×17=323", "needs_review": false, "correct_answer": "323"}]