[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 67 + 45", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "112"}, {"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: 13 × 11", "difficulty": "medium", "explanation": "Multiply: 13×11=143", "needs_review": false, "correct_answer": "143"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 16 × 8", "difficulty": "medium", "explanation": "Multiply: 16×8=128", "needs_review": false, "correct_answer": "128"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 17", "difficulty": "medium", "explanation": "Multiply: 13×17=221", "needs_review": false, "correct_answer": "221"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 2", "difficulty": "medium", "explanation": "Multiply: 2×2=4", "needs_review": false, "correct_answer": "4"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 6", "difficulty": "medium", "explanation": "Multiply: 4×6=24", "needs_review": false, "correct_answer": "24"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 14", "difficulty": "medium", "explanation": "Multiply: 5×14=70", "needs_review": false, "correct_answer": "70"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 9", "difficulty": "medium", "explanation": "Multiply: 14×9=126", "needs_review": false, "correct_answer": "126"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 19", "difficulty": "medium", "explanation": "Multiply: 12×19=228", "needs_review": false, "correct_answer": "228"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 3", "difficulty": "medium", "explanation": "Multiply: 5×3=15", "needs_review": false, "correct_answer": "15"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 12", "difficulty": "medium", "explanation": "Multiply: 8×12=96", "needs_review": false, "correct_answer": "96"}]