[{"id": 1, "type": "short_answer", "skill": "subtraction", "question": "Calculate: 292 − 140", "difficulty": "medium", "explanation": "Subtract by place value, borrowing as needed.", "needs_review": false, "correct_answer": "152"}, {"id": 2, "type": "multiple_choice", "skill": "subtraction", "options": ["152", "153", "432", "150"], "question": "What is 292 − 140?", "difficulty": "easy", "explanation": "292-140=152", "needs_review": false, "correct_answer": "152"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 6", "difficulty": "medium", "explanation": "Multiply: 19×6=114", "needs_review": false, "correct_answer": "114"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 8 × 10", "difficulty": "medium", "explanation": "Multiply: 8×10=80", "needs_review": false, "correct_answer": "80"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 13 × 2", "difficulty": "medium", "explanation": "Multiply: 13×2=26", "needs_review": false, "correct_answer": "26"}]