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Picturephone service, which will become available commercially in the 1970s, will at first probably be used by large business corporations.(47)It is already clear that "the next best thing to being there" is going to be a Picturephone call. (48)This "new light", first produced by scientists in 1960, can beam continuously and with extraordinary intensity.(49)In other words, they are thinking of using light for the same purpose radio waves are used—to transmit telephone calls, TV programs, and data messages from one point to another. With the expansion of Picturephone service and highspeed data communications between computers, present message-carrying capacities may soon become inadequate. As it turns out to be technically and economically&39; sound, the laser might prove to be a major breakthrough in telephone communications. Current research in telephone communications is so extensive and changes are coming about so rapidly that no one can predict with accuracy what the telephone of tomorrow will look like.(50)。 (46) A. But as Picturephone service becomes available, it will no doubt spread from the office to the home. B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by. C. For many people the most&39; exciting development in recent years is Picturephone service. D. One area that is being seriously considered is communications service "on the move". E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones. F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications. (47) A. But as Picturephone service becomes available, it will no doubt spread from the office to the home.B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by.C. For many people the most&39; exciting development in recent years is Picturephone service.D. One area that is being seriously considered is communications service "on the move".E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones.F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications. (48) A. But as Picturephone service becomes available, it will no doubt spread from the office to the home.B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by.C. For many people the most&39; exciting development in recent years is Picturephone service.D. One area that is being seriously considered is communications service "on the move".E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones.F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications. (49) A. But as Picturephone service becomes available, it will no doubt spread from the office to the home.B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by.C. For many people the most&39; exciting development in recent years is Picturephone service.D. One area that is being seriously considered is communications service "on the move".E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones.F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications. (50) A. But as Picturephone service becomes available, it will no doubt spread from the office to the home.B. Instead of using light to see by, telephone researchers are thinking of ways to use light to communicate by.C. For many people the most&39; exciting development in recent years is Picturephone service.D. One area that is being seriously considered is communications service "on the move".E. But there is at least one prediction that can be made with assurance: There will be more and more telephones in the future, and they will be better ones.F. Possibly the most significant research now being conducted is in the use of the laser beam in telephone communications.
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A.
被土壤胶体吸附
B.
溶解于水
C.
游离于土壤溶液中
D.
更易为植物吸收利用
【单选题】土壤速效磷又称为土壤有效磷,是指能被当季作物吸收利用的磷,关于土壤速效磷的测定方法,下列说法错误的是
A.
 同位素法是利用磷的同位素32P稀释法测土壤有效磷含量,是测定土壤速效磷的标准方法
B.
生物方法测定土壤中速效磷含量最直接,最可靠,缺点是耗时太长
C.
化学方法是选用适宜的提取剂来提取土壤中的有效磷,因为测定过程简便,测定结果与植物生长有较好的相关性,所以应用最为普遍
D.
阴离子交换树脂法是利用树脂可单方向从溶液中不断的吸附磷酸根,来模拟植物吸收磷的作用,有助于固相磷进入溶液,测得的结果很接近土壤中有效磷的含量。
E.
虽然土壤速效磷的测定方法有很多,但是对土壤速效磷含量的评价指标是一样的,所以不同的方法之间也可以进行土壤速效磷状况的比较。
【单选题】老年女性股骨头骨折后,发现左侧肘关节屈曲无力,前臂外侧皮肤感觉丧失,肱二头肌腱反射消失,可能受损伤的神经是
A.
胸长神经
B.
肌皮神经
C.
正中神经
D.
胸背神经
E.
桡神经
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A.
B.
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A.
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B.
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C.
具有医学专业专科学历,在医疗机构中工作满一年
D.
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E.
具有医学专业本科以上学历,在医疗机构中试用期满二年
【单选题】至少符合下列哪种情况才能参加执业医师资格考试
A.
具有医学专业本科以上学历,在医疗机构中工作满一年
B.
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C.
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D.
具有医学专业专科学历,在医疗机构中试用期满一年
【判断题】政府采购不是市场行为。( )
A.
正确
B.
错误
【单选题】政府采购中寻租现象的产生的原因中,( )是政府采购中寻租行为的重要动机。
A.
公权力对市场交易的介入
B.
追逐个人利益
C.
政府采购中形成的委托代理关系
D.
政府采购中形成的信息不对称
【单选题】低压开关的触点,在没有压力作用下是()的
A.
常开
B.
常闭
【判断题】政府采购制度是一套将政府购买活动强制推进市场竞争而且是充分竞争的制度,而不是为了保护行政特权和行政优势的制度。(    )
A.
正确
B.
错误
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