[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 33 + 97", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "130"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Identity property", "Distributive property", "Associative property", "Commutative 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: 7 × 5", "difficulty": "medium", "explanation": "Multiply: 7×5=35", "needs_review": false, "correct_answer": "35"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 20 × 3", "difficulty": "medium", "explanation": "Multiply: 20×3=60", "needs_review": false, "correct_answer": "60"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 5", "difficulty": "medium", "explanation": "Multiply: 16×5=80", "needs_review": false, "correct_answer": "80"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 8", "difficulty": "medium", "explanation": "Multiply: 3×8=24", "needs_review": false, "correct_answer": "24"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 18", "difficulty": "medium", "explanation": "Multiply: 18×18=324", "needs_review": false, "correct_answer": "324"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 9", "difficulty": "medium", "explanation": "Multiply: 13×9=117", "needs_review": false, "correct_answer": "117"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 9", "difficulty": "medium", "explanation": "Multiply: 10×9=90", "needs_review": false, "correct_answer": "90"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 17", "difficulty": "medium", "explanation": "Multiply: 9×17=153", "needs_review": false, "correct_answer": "153"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 7", "difficulty": "medium", "explanation": "Multiply: 13×7=91", "needs_review": false, "correct_answer": "91"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 4", "difficulty": "medium", "explanation": "Multiply: 8×4=32", "needs_review": false, "correct_answer": "32"}]