[Multiple Choices] Preparative chromatography is shown from following activity: O preparation of HPLC calibration solution. xylose purification from sugar mixture. O sugar solution concentration. sugar composition analysis in a fermentation broth. [Multiple Choices] If the signal to noise ratio of the sample is found to be considerably small, then the most appropriate action to mitigate this issue is by O increasing injection volume. decreasing injector temperature. O decreasing injection volume. o increasing injector temperature. [Multiple Choices] Certain phenomenon that occurs inside gas chromatography injector is O pressure increase of mobile phase. O sample dilution. sample adsorption into capillary pipe. sample separation from eluent. [Multiple Choices) The following action is not needed when gas chromatography samples are gaseous O heating the oven. O heating the syringe. O heating the injector. O heating the detector. [Multiple Choices] The following mixture is allowed to be injected into GC equipment without further treatment: O sugar and water. O ethanol and water. O vegetable oil and ethanol. O sugar and ethanol