小明同学利用圆珠笔杆、钢丝、细绳制成了如图所示的滑轮组用其匀速提升重物,不考虑摩

题型:选择题

问题:

小明同学利用圆珠笔杆、钢丝、细绳制成了如图所示的滑轮组用其匀速提升重物,不考虑摩擦、笔杆和绳重,下列说法正确的是(  )

A.拉细绳的力F等于钩码重力G的

B.拉细绳的力F等于钩码重力G的

C.拉细绳的力F等于钩码重力G的

D.拉细绳下降的距离是钩码上升高度的

考点:滑轮组及其工作特点滑轮(组)中拉力的计算
题型:选择题

阅读下面短文,从短文后各题所给的四个选项(A、B、C和D)中选出可以填入空白的最佳选项,并在答题卡上将该项涂黑。

I have always believed the saying , “Any man can be a father, but it   31   someone special to be a dad.” This is true. Since the   32  of my son, Joshua, things have changed a lot in my life, but the  33  have been good! My wife and I have been through many  34   moments which have made both of us stronger.

My son was born with a serious breathing problem and he couldn’t keep his  35  down. He was put on several different medications,   36  he did not get any better. My wife and I were both told many times by people that Joshua   37  he was born early; he had not   38  much weight since he was born.

As time progressed his regular doctor  39   my wife and me to visit Dr. Eid, a specialist in Louisville. He was   40  by my son’s condition and so we were sent to Louisville’s Children’s Hospital . Joshua   41  many different checkups. The   42  spent there was very demanding for my wife and me. But we did make it   43 . Our son Joshua was diagnosed (诊断) with asthma (哮喘) , and with acid reflux syndrome (酸回流综合症). After the treatment, his  44   began to improve slowly.

Joshua is 1 year and 1 month old now and his progress has been   45  --- he is up to 27 pounds now. I keep telling my wife that if he keeps  46  like this he might become a football _____47   someday. There is a saying that has   48   me get through these troublesome times, “Problems will either  49    you or break you.”  When you think the   50  hours are upon you, remember the dawn is just in sight.

小题1:

A.takes

B.asks

C.tells

D.brings小题2:

A.return

B.illness

C.birth

D.death小题3:

A.doctors

B.friends

C.causes

D.changes小题4:

A.boring

B.challenging

C.exciting

D.puzzling小题5:

A.food

B.water

C.weight

D.medicine小题6:

A.so

B.but

C.since

D.until小题7:

A.looked about

B.looked for

C.looked like

D.looked at小题8:

A.gained

B.lost

C.kept

D.raised小题9:

A.followed

B.ordered

C.invited

D.advised小题10:

A.angered

B.shocked

C.disappointed

D.scared小题11:

A.went into

B.put into

C.went through

D.broke through小题12:

A.time

B.money

C.hour

D.holiday小题13:

A.out

B.down

C.off

D.through小题14:

A.diet

B.study

C.health

D.weight小题15:

A.great

B.slow

C.little

D.enough小题16:

A.walking

B.running

C.training

D.growing小题17:

A.supporter

B.player

C.coach

D.fan小题18:

A.left

B.moved

C.helped

D.watched小题19:

A.cheat

B.make

C.beat

D.find小题20:

A.easiest

B.latest

C.brightest

D.darkest

题型:选择题

两个因数分别是25和5,积是______,如果把因数5改成50、500,积分别是______、______.

题型:选择题

按国债资金的来源将国债划分为( )。

A.凭证式国债和记账式国债
B.本币国债和外币国债
C.内债和外债
D.实物国债和黄金国债

题型:选择题

成年人血中胰岛素样生长因子-1含量明显升高常可引起的病症是()

A.侏儒症

B.呆小症

C.佝偻病

D.肢端肥大症

E.糖尿病

题型:选择题

实验动物鸡主要的人兽共患病种类有()和鹦鹉病。

A.肾综合征出血热

B.土拉伦菌病

C.禽流感

D.非典型肺炎

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