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问题 选择题

下列化学用语表示2个氢原子的是：

A．H2

B．2H

C．2H2

D．2H＋

答案

B.

本题考查的是化学符号及其周围数字的意义，元素符号、化学式前面放上了化学计量数，只表示微观意义。

A、H2表示：①氢气这种物质；②氢分子；③每个氢分子中含有两个氢原子，故A不符合；

B、2H表示2个氢原子，故B符合；

C、2H2表示两个氢分子，故C不符合；

D、2H+表示2个氢离子，故D不符合。故选B

阅读理解

BORDER
CROSSINGS
While there are no restrictions on the amount of money that you can bring across the border, you must report to both the US and Canadian border
services amounts equal to or greater than $10.000.
PERSONAL EXEMPTIONS（免税）ON PURCHASES
AMERICANS RETURNING TO THE US
Less than 48 hours: $ 200 US
48 hours or more:  $ 800 US duty-free personal exemption.
next $ 1.000 US at 3%
Including up to 100 cigars and 100 cigarettes.
CANADIANS RETURNING TO CANADA
Less than 24 hours: $ 50 CAN
48 hours or more:  $ 400 CAN
Including up to 100 cigars and 200 cigarettes.
7 days or more: $ 750 CAN
Including up to 100 cigars and 200 cigarettes.
DOCUMENTATION NEEDED FOR BORDER CROSSING
LAND OR SEA TO THE US(INCLUDING FERRIES)
A valid passport or passport card, or a NEXUS card.
(A NEXUS card is a Trusted Traveler Program that provides quick travel for pre-approved, low risk travelers through special lanes.)
A recent Washington State, New York or BC driver’s license.
Note: Children 15 years of age and younger require only a birth certificate or copy.(Certified copies are not required but are advised.)
AIR TRAVEL TO THE US
A valid passport, an Air NEXUS card, or a U.S. Coast Guard Merchant Marine Document.
小题1:If a Canadian who is on a 7-day trip to New York buys $ 800 CAN worth of goods, how much should he pay tax on when returning home?
A．$ 800 CANB．$750 CANC．$ 400 CAND．$ 50 CAN
小题2:For an American citizen on a 2-day tour of Canada, how much tax does he have to pay on $ 1.600 US worth of purchases when returning to the US?
A．$ 24 USB．$ 48 USC．$52 USD．$ 200 US
小题3:What documentation should a couple with a 7-year-old child carry when they drive a car from Canada to America?
A．A BC driver’s license, an Air NEXUS card, and a birth certificate.
B．An Air NEXUS card, a U.S. Coast Guard Merchant Marine Document, and a birth certificate.
C．Two valid passport cards and a certified copy of a birth certificate.
D．A NEXUS card, a U.S. Coast Guard Merchant Marine Document., and a certified copy of a birth certificate.
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单项选择题

下面哪项是：Bleuter描述的精神分裂症的特征性症状（）

A.牵连观念

B.被害妄想

C.幻听

D.妄想性知觉

E.矛盾意向
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