【判断题】Sometimes, there are small revoleved features in shafts that need to be represented with removed sections. In these cases, when cutting planes go through the axes of the small holes or pits, the rela...
【单选题】In such cases, either chemical methods of separation with the general techniques of chemical analysis must be applied in order to eliminate the interfering effects of these constituents or, as is comm...
【单选题】Most reproduction of plants is accomplished through germination of seeds, but sometimes this is not possible or the process is too lengthy for commercial purposes. In these cases, man steps in and use...