【简答题】陶是人类最早利用化学反应制造的人造材料,青铜是人类最早利用化学反应制造的金属材料。陶器. 青铜器及铝器的广泛使用,极大地促进了人类社会的发展。请回答下列问题: (1)陶. 铜. 铁等材料的生产离不开火,火即所谓的燃烧,其实质是一种 反应;而铜和铁的冶炼,主要是利用 反应把铜和铁从其的化合物中转化出来。 (2)地壳中铝. 铁的含量分别位列金属的第I和第2位,远多于铜,但铜却是人类最早冶炼出的金属,已...
【多选题】Ethical issues of organ donation include:
B.
voluntary and involuntary organ donation
D.
organ trafficking and black market
【多选题】What are the ethical issues in organ transplantation?
D.
Alternative organ sources
【简答题】化学与材料 陶是人类最早利用化学反应制造的人造材料,青铜是人类最早利用化学反应制造的金属材料.陶器、青铜器及铝器的广泛使用,极大地促进了人类社会的发展.请回答下列问题: (1)陶、铜、铁等材料的生产离不开火,火即所谓的燃烧,其实质是一种(填反应类型)______反应;而铜和铁的冶炼,主要是利用(填反应类型)______反应把铜和铁从其的化合物中转化出来.制陶的原料是黏土,其主要成分是二氧化硅、氧化...
【判断题】月末企业银行存款的实有余额为银行对账单余额加上企业已收、银行未收款项,减去企业已付、银行未付的款项。
【单选题】When he went out, he would wear sunglasses () nobody would recognize him.
【单选题】There would be many more organ donors if ______.
A.
laws are designed to encourage organ recycling
B.
people can't legally prevent a family member from donating his organ
C.
doctors are more willing to ask for donations
D.
transplant surgery is more successful