[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 68 + 11", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "79"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Identity property", "Associative property", "Commutative 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: 3 × 13", "difficulty": "medium", "explanation": "Multiply: 3×13=39", "needs_review": false, "correct_answer": "39"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 10", "difficulty": "medium", "explanation": "Multiply: 9×10=90", "needs_review": false, "correct_answer": "90"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 11", "difficulty": "medium", "explanation": "Multiply: 2×11=22", "needs_review": false, "correct_answer": "22"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 17", "difficulty": "medium", "explanation": "Multiply: 5×17=85", "needs_review": false, "correct_answer": "85"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 19", "difficulty": "medium", "explanation": "Multiply: 9×19=171", "needs_review": false, "correct_answer": "171"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 11", "difficulty": "medium", "explanation": "Multiply: 3×11=33", "needs_review": false, "correct_answer": "33"}]