[{"id": 1, "type": "short_answer", "skill": "computation", "question": "Calculate: 49 + 54", "difficulty": "medium", "explanation": "Add systematically.", "needs_review": false, "correct_answer": "103"}, {"id": 2, "type": "multiple_choice", "skill": "properties", "options": ["Commutative property", "Identity property", "Distributive property", "Associative 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: 2 × 16", "difficulty": "medium", "explanation": "Multiply: 2×16=32", "needs_review": false, "correct_answer": "32"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 11", "difficulty": "medium", "explanation": "Multiply: 17×11=187", "needs_review": false, "correct_answer": "187"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 17 × 18", "difficulty": "medium", "explanation": "Multiply: 17×18=306", "needs_review": false, "correct_answer": "306"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 2", "difficulty": "medium", "explanation": "Multiply: 12×2=24", "needs_review": false, "correct_answer": "24"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 10 × 9", "difficulty": "medium", "explanation": "Multiply: 10×9=90", "needs_review": false, "correct_answer": "90"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 10", "difficulty": "medium", "explanation": "Multiply: 13×10=130", "needs_review": false, "correct_answer": "130"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 7 × 18", "difficulty": "medium", "explanation": "Multiply: 7×18=126", "needs_review": false, "correct_answer": "126"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 12", "difficulty": "medium", "explanation": "Multiply: 4×12=48", "needs_review": false, "correct_answer": "48"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 19", "difficulty": "medium", "explanation": "Multiply: 11×19=209", "needs_review": false, "correct_answer": "209"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 6", "difficulty": "medium", "explanation": "Multiply: 14×6=84", "needs_review": false, "correct_answer": "84"}]