如图所示,在x轴上方存在着垂直于纸面向里、磁感应强度为B的匀强磁场.一个不计重力

题型:选择题

问题:

如图所示,在x轴上方存在着垂直于纸面向里、磁感应强度为B的匀强磁场.一个不计重力的带电粒子从坐标原点O处以速度v进入磁场,粒子进入磁场时的速度方向垂直于磁场且与x轴正方向成120°角,若粒子从x轴上的P点射出磁场,已知p点与O点的距离为a,则该粒子的比荷和所带电荷的正负是(  )

A.v/aB,正电荷

B.v/2aB,正电荷

C.v/aB,负电荷

D.v/2aB,负电荷

考点:带电粒子在匀强磁场中的运动
题型:选择题

“爱的奉献”赈灾义演晚会,共为四川灾区募捐善款1514290000元.这个数读作______元,改写成用“亿”作单位的数是______元.

题型:选择题

伤寒、副伤寒预防原则为

控制传染源()

A.及时发现病人,隔离,消毒与治疗

B.对有关从业人员粪便与Vi抗体检测

C.对密切接触者进行医学观察

D.A、B、C三者同时进行

E.不予处理

题型:选择题

Wugging, or web use giving, describes the act of giving to charity at no cost to the user. By using Everyclick.com, which is being added to a number of university computers across the UK, students can raise money every time they search, but it won’t cost them a penny.

Research shows that students are extremely passionate about supporting charity — 88% of full time students have used the Internet to give to charity. This age group is often the least likely to have their own income. 19% of 22 to 24 year olds have short-term debts of more than £5,000. With rising personal debt levels in this age group, due to university tuition fees or personal loans and a lack of long-term savings, traditional methods of donating to charity are often not appealing (有感染力的) or possible.

Beth Truman, a 21 year old recent university graduate, has used Everyclick.com to donate to her chosen charity, the RSPCA, for two years and has seen the “wugging” movement grow in popularity with students. “When you’re at university you become more socially aware, but it’s sometimes hard to give to others when you have little money yourself,” says Beth. “Wugging is great for people in this age group as it allows them to use the technology on a daily basis to give to charity, without costing them a single penny.”

Wugging is perfect for people who want to be more socially aware and supportive but don’t feel they have the means to do so. Students using the web can raise money for causes they care about without costing them anything in terms of time or money, and charities get a valuable source of funding.

Everyclick.com works like any other search engine, allowing users to search for information, news and images but users can decide which of the UK’s 170,000 charities they would like to support through their clicks. Everyclick.com then makes monthly payments to every registered charity. Launched in June 2005, Everyclick.com is now the eighth largest search engine and one of the busiest charity websites in the UK.

小题1:According to the passage, “wugging” is actually ______.

A.a website

B.a charity-related action

C.a school organization

D.a student movement小题2:In the case of charity, Everyclick.com ______.

A.frees students of the financial worries

B.receives much money from students

C.offers valuable information to students

D.praises students for their money-raising小题3: What does Beth Truman think of the “wugging” movement?

A.It makes Everyclick.com popular in the UK.

B.It becomes easy to do charity because of it.

C.It results in students’ more social awareness.

D.It helps students to save money.小题4:From the passage, we can conclude that ______.

A.most full time students do charity on the Internet every day

B.Everyclick.com helps students pay for the college education

C.“wugging” is a win-win idea for both students and charities

D.Everyclick.com is the most successful search engine in the UK小题5:What would be the best title for this passage?

A.“Wugging”, a new popular term on the Internet.

B.British people show strong interest in charity.

C.More Britain charities benefit from the Internet.

D.Students raise money for charity by “wugging”.

题型:选择题

腹中填入鱼粉()

A.白附片

B.海马

C.青黛

D.天麻

E.红花

题型:选择题

含有蚕丝纤维40%、粘胶长丝40%、尼龙短纤20%的起绒针织物(幅宽60毫米)

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