试题与答案

甲、乙、丙三人同时由A地出发去B地.甲骑自行车到C地(C是A、B之间的某地),然

题型:填空题

题目:

甲、乙、丙三人同时由A地出发去B地.甲骑自行车到C地(C是A、B之间的某地),然后步行;乙先步行到C点,然后骑自行车;丙一直步行.结果三人同时到达B地.已知甲步行速度是每小时7.5km;乙步行速度是每小时5km.甲、乙骑自行车的速度都是每小时10km,那么丙步行的速度是每小时______km.

答案:

设A、B两地相距Skm,A、C两地相距xkm,丙每小时走Vkm,

x
10
+
S-x
7.5
=
x
5
+
S-x
10
=
S
V

3x+4(S-x)=6x+3(S-x),

解得x=

S
4

S
V
=
S
4
5
+
S-
S
4
10
=
S
8
,∴V=8(km/h).

故答案为8.

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题型:阅读理解

B

Shopping carts are such a ubiquitous presence in stores today that it is hard to imagine a time without them.And yet it wasn’t until the year 1937 when the first shopping cart was introduced.

The shopping cart was the brainchild of Sylvan Goldman,the owner of a grocery food chain in 0klahoma.Goldman noticed that his customers struggled to carry their food in heavy hand-held baskets.He decided there must be an easier way for his costomers to carry the food around in his supermarkets.Observing a folding chair, Goldman decided to use that as the prototype for his new shopping cart.

With the aid of a mechanic, Fred Young ,Goldman designed the first shopping cart based on the folding chair.Wheels were placed where the bottoms of the chair legs were. In place of the chair seat, Young and Goldman , placed two metal baskets on top of each other. This cart could be stored by folding it up like a folding chair.

At first there was a bit of difficulty getting the public to accept shopping carts.Men thought using them was effeminate(女人气的)while younger women considered the use of the shopping carts to carry products around to be somewhat unstylish.Goldman solved this problem by hiring men and women models to use shopping carts in his stores.In addition,store     greeters instructed customers in how to use the shopping carts.In short order,the shopping carts became incredibly popular because it made shopping much easier for customers.By 1940 the popularity of shopping carts had grown to such an extent that there was a 7 year waiting list in store orders for new shopping carts.

45.. The underlined word“ubiquitous”is closest in meaning to”_________”.

A.strange    B.pleasant       C.common       D.possible

46.. The idea of shopping carts came from _____________.

A.Goldman’ s imagination           B.customers’needs

C.Fred Young’ s suggestion           C.other shops’examples

47.. Why was it difficult to get the public to accept shopping carts at first?

A.Both men and women were afraid they would not look good if they used them.

B.  People thought it unnecessary to use them because they never did much shopping.

C.  The early shopping carts were too difficult to use.

D. Only men and women models were supposed to use such modern things.

48.. How popular did Goldman’s invention finally become?

A.Men and women models used shopping carts in his stores.

B.Store greeters instructed customers in how to use the shopping carts.

C.Some stores had to wait several years to get his shopping carts.

D.His shopping carts had improved so much that both men and women liked to use them.

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