两个完全一样的直角三角形，拼成的图形不可能是（ ） A．长方形 B．正方形 C． 发布时间：2017-06-13 13:08 │ 来源：www.tikuol.com 题型：多选题 问题： 两个完全一样的直角三角形，拼成的图形不可能是（ ）A．长方形B．正方形C．等腰三角形D．五边形
题型：多选题 下列哪项不是固定义齿修复后产生食物嵌塞的原因（）A．咬合不平衡，前伸早接触B．邻面无接触或接触不良C．平面与邻牙不一致，形成斜向邻面的斜面D．对颌牙有充填式牙尖E．修复体有悬突或龈边缘不密合 查看答案
题型：多选题 关于呼吸调节的叙述，错误的是（）A.呼吸肌节律运动受控于中枢神经系统的呼吸中枢B.呼吸中枢的神经细胞群产生和调节呼吸运动C.血液中二氧化碳含量增加，将刺激呼吸加速D.呼吸运动不受神经性反射调节E.血液中pH值降低，将刺激呼吸加速 查看答案
题型：多选题 患者妊娠2个多月，近日 * * 少量出血，小腹坠及腰痛，夜尿多，神疲乏力，面色晦暗，曾自然流产2次，小产2次，舌淡，苔白，脉沉尺弱。首先应考虑的诊断是（）A.胎动不安B.胎漏C.滑胎D.堕胎E.小产 查看答案
题型：多选题 阅读理解。A. Control of respiration B. Basic tips for preserving cut flowers C. Role of respiration D. Most important aspect of flower care E. Need for clean water F. Ways of stopping respiration1. ( ) While everybody enjoys fresh cut flowers around his house, few people know how to keep them for aslong as possible. This may be done by keeping in mind a few simple facts. The key to keeping fresh cut flower for a week or more without preservatives ( which contain biocides (杀虫剂) that kill bacterial and fungus) is to keep the water fresh and the stems free of air pockets so they can continue to draw up water. 2. ( ) An important thing to remember about cut flowers is that they are sensitive to temperature. For example, studies have shown that cut carnations retain their freshness eight times longer when kept at 12℃ than whenkept at 26℃. Keeping freshly harvested flowered at the right temperatures is probably the most important aspect of flower care. 3. ( ) The process by which flowers consume oxygen and produce carbon dioxide, called respiration (呼吸),supplies the energy the flower needs to give the flower its shape and color. The making of seeds also dependson this energy. While all living things respire, flowers have a high level of respiration. A result of all this respiration is heat, and for flowers the level of heat relative to the mass of the flower is very high. Respirationalso brings about the eventual death of the flower. Thus the greater the level of respiration, the sooner theflower dies. 4. ( ) How, then, to control the speed at which flowers die? By controlling respiration. How is respiration controlled? By controlling temperature, we know that respiration produces heat, but the reverse (反面) isalso true. Thus by keeping low temperatures, respiration is reduced and the cut flower will age more slowly.5. ( ) Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to "drink" water that is dirty or otherwise polluted. Even when water looks and smells clean, it almost certainly contains harmful substances that can endanger the flowers. To rid the water of theseunwanted substances, chlorine bleach (含氯漂白剂) can be used in small quantities. It is recommended that 15 drops of chlorine bleach be added to each liter of water. The water and solution (溶液) should also bereplaced each day. 查看答案
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