[{"id": 1, "type": "short_answer", "skill": "multiplication", "question": "Calculate: 12 × 7", "difficulty": "medium", "explanation": "12 groups of 7.", "needs_review": false, "correct_answer": "84"}, {"id": 2, "type": "multiple_choice", "skill": "multiplication", "options": ["96", "19", "77", "84"], "question": "What is the product of 12 and 7?", "difficulty": "easy", "explanation": "12×7=84", "needs_review": false, "correct_answer": "84"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 4 × 12", "difficulty": "medium", "explanation": "Multiply: 4×12=48", "needs_review": false, "correct_answer": "48"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 12 × 18", "difficulty": "medium", "explanation": "Multiply: 12×18=216", "needs_review": false, "correct_answer": "216"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 10", "difficulty": "medium", "explanation": "Multiply: 3×10=30", "needs_review": false, "correct_answer": "30"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 15 × 7", "difficulty": "medium", "explanation": "Multiply: 15×7=105", "needs_review": false, "correct_answer": "105"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 14", "difficulty": "medium", "explanation": "Multiply: 13×14=182", "needs_review": false, "correct_answer": "182"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 19", "difficulty": "medium", "explanation": "Multiply: 2×19=38", "needs_review": false, "correct_answer": "38"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 5 × 16", "difficulty": "medium", "explanation": "Multiply: 5×16=80", "needs_review": false, "correct_answer": "80"}, {"id": 10, "type": "short_answer", "skill": "computation", "question": "Calculate: 2 × 17", "difficulty": "medium", "explanation": "Multiply: 2×17=34", "needs_review": false, "correct_answer": "34"}, {"id": 11, "type": "short_answer", "skill": "computation", "question": "Calculate: 9 × 9", "difficulty": "medium", "explanation": "Multiply: 9×9=81", "needs_review": false, "correct_answer": "81"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 6", "difficulty": "medium", "explanation": "Multiply: 3×6=18", "needs_review": false, "correct_answer": "18"}]