Popular music is different from classical music and folk music in that（） ["it is very noisy","it is anonymous","it is written as a commercial product for mass distribution","it is an individual artistic creatio"]
在合成代谢中，能量的直接来源是（）中的高能磷酸键的水解。
汉语普通话中，哪一个音学特征没有区别意义的功能（）。 ["音质","音高","音强","音长"]
病人认知技能和情感相对完整，妄想和幻觉为主要症状，这是（） ["偏执型精神","青春型精神分裂症","紧张型精神分裂症","单纯型精神分裂症"]
关于齿轮泵的起动，下列操作正确的是（） ["齿轮泵具有自吸能力，可以进行泵内无油起动","进、排出阀应全开起动","进口阀应全开，排出阀应在起动过程中慢慢开启","起动时，安全阀或旁通阀须开启"]
空间艺术
