[{"id": 1, "type": "short_answer", "skill": "area", "question": "Find the area of a rectangle: length=10, width=8", "difficulty": "medium", "explanation": "A=l×w=10×8=80 sq units.", "needs_review": false, "correct_answer": "80"}, {"id": 2, "type": "multiple_choice", "skill": "perimeter", "options": ["18", "80", "40", "36"], "question": "Find the perimeter of a rectangle: length=10, width=8", "difficulty": "medium", "explanation": "P=2(l+w)=2(10+8)=2(18)=36", "needs_review": false, "correct_answer": "36"}, {"id": 3, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 7", "difficulty": "medium", "explanation": "Multiply: 6×7=42", "needs_review": false, "correct_answer": "42"}, {"id": 4, "type": "short_answer", "skill": "computation", "question": "Calculate: 6 × 2", "difficulty": "medium", "explanation": "Multiply: 6×2=12", "needs_review": false, "correct_answer": "12"}, {"id": 5, "type": "short_answer", "skill": "computation", "question": "Calculate: 19 × 5", "difficulty": "medium", "explanation": "Multiply: 19×5=95", "needs_review": false, "correct_answer": "95"}, {"id": 6, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 10", "difficulty": "medium", "explanation": "Multiply: 18×10=180", "needs_review": false, "correct_answer": "180"}, {"id": 7, "type": "short_answer", "skill": "computation", "question": "Calculate: 18 × 13", "difficulty": "medium", "explanation": "Multiply: 18×13=234", "needs_review": false, "correct_answer": "234"}, {"id": 8, "type": "short_answer", "skill": "computation", "question": "Calculate: 11 × 11", "difficulty": "medium", "explanation": "Multiply: 11×11=121", "needs_review": false, "correct_answer": "121"}, {"id": 9, "type": "short_answer", "skill": "computation", "question": "Calculate: 14 × 8", "difficulty": "medium", "explanation": "Multiply: 14×8=112", "needs_review": false, "correct_answer": "112"}, {"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: 17 × 19", "difficulty": "medium", "explanation": "Multiply: 17×19=323", "needs_review": false, "correct_answer": "323"}, {"id": 12, "type": "short_answer", "skill": "computation", "question": "Calculate: 3 × 4", "difficulty": "medium", "explanation": "Multiply: 3×4=12", "needs_review": false, "correct_answer": "12"}]