【单选题】Statistics over four consecutive years showed that four percent more automobile accidents happened in California during the week following the switch to daylight saving time and during the week follow...
A.
Drivers in California as well as those in the rest of the United States have similar driving patterns.
B.
The observed increases in accident rates are due almost entirely to an increase in the number of minor accidents.
C.
Four years is not a sufficiently long period of time over which to judge the phenomenon described.
D.
There are no other factors such as school vacations or holiday celebrations that cause accident rates to rise during these weeks.
E.
A time change at any other time of year would not produce a similar increase in accident rates.
【单选题】二十五岁已婚妇女,尚未生育,此次停经2.5月伴少量阴道出血3天就诊,医生检查子宫大小明显超出停经月份如果检查为葡萄胎,处理上哪项是错误的()
【单选题】Scientists generally agree that the earth's climate will warm up over the next 50 to 100 years ______ it has warmed in the 20000 years since the Ice Age.
【单选题】___ years ago, the population of China was over 20 million.
【单选题】Scientists generally agree that the Earth's climate will warm up over the next 50 to 100 years ______it has warmed in the 20,000 years since the Ice Age.
【简答题】某妇女,53岁,放置宫内18年,现绝经1年,到门诊要求取出。妇科检查:外阴发育正常,已婚已产型;阴道通畅,黏膜略平滑,分泌物无色、量少;宫颈光滑,大小正常;宫体前倾前屈位,正常大小,活动良好;双附件未触及异常。该妇女在取器前应进行的必要检查是A、血常规检查 B、心电图检查 C、阴道涂片检查 D、腹部CT检查 E、妇科B超检查 若取器过程中发现嵌顿,分析其发生的可能原因是A、放置时...
【判断题】n型半导体指在Si、Ge等四价元素中掺入少量五价元素P、Sb、Bi、As