非专业人问个问题,根据标准生成焓定义,C+O2=CO2,标准生成焓为-393.5KJ/mol,其中C为石墨.

英语翻译和文言文遵守的原则是一样的，即：信、达、雅。
句子翻译对一半就可得一半的分
关键词错了会影响整个句子的意思，顶多能的三分之一的分数
大体意思对，语序不好扣掉的分数应该不会多

早晨：太阳出来的时候．
晚上：天黑．
白天：太阳出来到天黑前
黑夜：从天黑到太阳出来以前

事实上这个问题中学竞赛涉及到的基础知识也还不是很足够,X染色体失活一直是细胞生物学的前沿热门领域.
从发育的角度讲,X染色体的失活发生在胚胎着床后,从囊胚期到原肠作用前,这时候发育为个体的内细胞团或上胚层的细胞已经非常多,而且发育参与到什么组织在头尾腹背决定前是随机的.X染色体随机失活后并不会造成一只眼球完全由某种致病基因的X染色体主宰的情况,或者说这是一个小概率事件.
X染色体的表达模式如今仍然是争议很大的领域,因此我们这种做研究的人给出的答案可能和出题的老学究会有区别.

老师算式对.但答案好像不对,应为F=λy(2a+g).因为v`2=ya而不是2ya.
你的ma=λya =λydv/dt
老师的ma=d(mv)/dt=d(λyv)/dt=λd(yv)/dt=λvdy/dt+λydv/dt
你的ma里面缺λvdy/dt项,它是冲量公式mv=Ft得来的,冲量是力的时间累积效应的量度,通过他可以计算出冲量力的大小,你的公式里只有λydv/dt这...

如何不限制题材，就用这个吧：
Report on how todecrease the high staff leaving rate in our comapny
Introduction:
The aim of this report is to analyse the staff leaving in our company ,try to find the reason ,thenput forward some solutions.
Findings:
Over the last two years, the number of the staff leaving in our company raisedrapidly from 5 to 20. On the country, compared with our competitor, it was muchless leaving, about 3 for each year. The reasons involve bonus, holiday andtraining after the research among the staff. They request more training,especially on personal capability and certificates, more paid holiday and abonus schemes(not just applied to senior management, but also to basic level).
Recommendations:
Based on the current conditions, more paid holiday should be available,training is a win-win strategy for both thecompany and staff, which makes the staff more efficient in work. In addintion,to establish a reasonable bonus schemes is a good idea to motivate the staffand get them feel valuable.
In my opinion, stuff training and bonus schemes are both available approachesto decrease the high staff leaving in our company.

甲的书只有2种可能 就是100本和200本
这样乘以13%才有整数
如果甲是200本的话
那么乙就是60本
而60乘以12.5%等于7.5
那书没有一半的
假如甲是100本
那乙就是160本
160乘以12.5%等于20刚好符合
所以甲有100本
即非专业的书有87本
希望答案对你有所帮助,请予以好评和右上角的采纳.