{
  "id": "S307",
  "type": "单选题",
  "type_code": "single",
  "stem": "均值为40，变异系数为0.4，则标准差是（ ）。",
  "stem_text": "均值为40，变异系数为0.4，则标准差是（ ）。",
  "options": [
    {
      "key": "A",
      "text": "100"
    },
    {
      "key": "B",
      "text": "0.01"
    },
    {
      "key": "C",
      "text": "16"
    },
    {
      "key": "D",
      "text": "4"
    }
  ],
  "options_text": [
    {
      "key": "A",
      "text": "100"
    },
    {
      "key": "B",
      "text": "0.01"
    },
    {
      "key": "C",
      "text": "16"
    },
    {
      "key": "D",
      "text": "4"
    }
  ],
  "answer_keys": [
    "C"
  ],
  "answer_display": "C",
  "answer_texts": [
    "16"
  ],
  "sources": [
    {
      "edition": "第17届",
      "edition_num": 17,
      "no": 34,
      "uid": "17-034",
      "file": "17届市调大赛本科组模拟题.docx"
    }
  ],
  "source_display": "第17届 第34题",
  "source_count": 1,
  "images": [],
  "warnings": [],
  "conflict": null,
  "url": "/q/S307.html"
}