[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 36 + 33", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "69"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Associative property", "Commutative property", "Distributive 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 × 18", "difficulty": "medium", "explanation": "Multiply: 12×18=216", "needs_review": false, "correct_answer": "216"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 12", "difficulty": "medium", "explanation": "Multiply: 4×12=48", "needs_review": false, "correct_answer": "48"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 20 × 18", "difficulty": "medium", "explanation": "Multiply: 20×18=360", "needs_review": false, "correct_answer": "360"}]