[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 40 + 23", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "63"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Associative property", "Distributive property", "Commutative 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: 16 × 15", "difficulty": "medium", "explanation": "Multiply: 16×15=240", "needs_review": false, "correct_answer": "240"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 16", "difficulty": "medium", "explanation": "Multiply: 7×16=112", "needs_review": false, "correct_answer": "112"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 4", "difficulty": "medium", "explanation": "Multiply: 11×4=44", "needs_review": false, "correct_answer": "44"}]