题目内容

Hess定律只能适用于等压反应热的计算。( )

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已知某药物按一级反应分解，在体温37℃时，反应速率常数为0.36h^-1。若服用该药物0.20g，问该药物在胃中停留多长时间方可分解80%？

证券交易所对债券上市实行上市推荐人制度，债券在证券交易所申请上市，必须由2～3个证券交易所认可的机构推荐并出具上市推荐书。（）

根据以下内容回答题：
Everyone wants to be healthy and happy．（1），illness or accidents mayoccur without any notice．Frequently the person who is（2）can be cared for at home if there is someone capable of looking after him under the doctor’s（3）．Sometimes arrangements can be made for a visiting nurse to give the necessary （4）once a day，or often，．if necessary．The responsible one in the home carries on with the rest of the care during the（5）between the nurses visits． The rapid diagnosis（诊断）and immediate treatment on the spot of an accident or sudden illness，（6）awaiting the arrival of doctors，is called the first aid and quite distinct from the home nursin9． When illness does come，the whole family is（7）．Many adjustments have to be made，but the family routine needn’t be（8）completely．Often it can be rearranged with home duties simplified to save time and energy，thus reducing strain on the family． The（9）responsibility for giving nursing care is usually assured by one person，frequently the mother．（10），in order that she may have some much needed rest，or in case she herself is ill，other members of the family should learn how to help when sickness occurs．
1.

Apparently
B. Unfortunately
C. Naturally
D. Occasionally

放射性同位素钋进行β衰变时，经过15天后，它的量减少了7.32%。试求此放射性同位素的衰变速率常数和半衰期，并计