同学探究镀铜的铁画中铁元素在生铁中的含量进行如下实验:取一定质量含96%生铁的镀

题型:计算题

问题:

同学探究镀铜的铁画中铁元素在生铁中的含量进行如下实验:取一定质量含96%生铁的镀铜铁画边角料。将该边角料磨成粉末,放入足量的稀盐酸中,待反应结束后过滤,将残渣洗涤、烘干、在空气中充分灼烧,最终得到0.3 g黑色固体,该固体比灼烧前减少了0.1 g(已知金属在灼烧过程中生成相应的氧化物)。求铁在生铁中的质量分数。

考点:化学反应方程式的计算
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How can you step into the lab with your shoes on? You're _____ to take them off before you enter it. I told you so!

A. expected
B. supposed
C. disagreed
D. permitted
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下面文章有5处需要添加小标题。请从以下选项(A、B、C、D、E和F)中选出符合各段意思的小标题,并填写在答题纸上将相应位置。选项中有一项是多余选项。
A. Classroom participation
B. Differences in American university education
C. Examination system
D. Competition among students
E. Honest policy in students' school work
F. Students' responsibility for learning
小题1:There is considerable variety in university classrooms in the United States. Because of diverse teaching methods and non-standardized curricula (课程), no two courses are the same.    Undergraduate courses are considerable different from graduate courses. The classroom atmosphere in expensive, private universities may differ from that in community colleges, which are free and open to everyone.
小题2:Participation in the classroom is not only accepted but also expected of the student in many courses. Some professors base part of the final grade on the student's oral participation. Although there are formal lectures during which the student has a passive role (i.e., listening and taking notes), many courses are organized around classroom discussions, student questions, and informal lectures.
小题3:Many teachers believe that the responsibility for learning lies with the student. (Courses are not designed merely for students to pass exams.) The ideal student is considered to be one who is motivated to learn for the sake of learning, not the one interested only in getting high grades.
小题4:Ideally, the teacher-student relationship at universities is characterized by trust. Thus, cheating on tests, Plagiarizing (抄袭) in written work, presenting other's ideas as original, and turning in homework completed by someone else are all prohibited (禁止).
小题5:Relationships between students in the classroom can be cooperative or competitive. International students should not hesitate to ask for help if it is needed. in classes where such a grading curve is used, students may be reluctant to share lecture notes or information for fear that their own grades will suffer.
题型:计算题

肺癌压迫喉返神经可发生()

A.声音嘶哑

B.上腔静脉阻塞综合征

C.吞咽困难

D.霍纳(Horner)综合征

E.血性胸腔积液

题型:计算题

我国国家工作人员在我国领域外犯我国刑法规定之罪,下列说法正确的是( )。

A.情节显著轻微危害不大的,可以不追究刑事责任
B.按犯罪地法律不受处罚的,可以不追究刑事责任
C.任何情况下都要追究其刑事责任
D.最高刑为3年以下有期徒刑的,应当不追究刑事责任

题型:计算题

假定窗体上有一个标签,名为Labe11,为了使该标签透明并且没有边框,则正确的属性设置为______ 。

A.Labe11.BackStyle=0
Labe11.Borderstyle=0

B.Labe11.BackStyle=1
Labe11.Bordkrstyle=1

C.Labe11.BaekStyle=True
Labe11.BorderStyle=True

D.Labe11.BackStyle=False
Labe11.BOrderstyle=False

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