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问题 选择题

把一个“12V 6W”的灯泡接入电路中，若通过灯泡的电流是0.3A，则灯泡的实际功率（　　）

A．等于6W

B．大于6W

C．小于6W

D．无法判断

答案

灯泡的电阻为：

R=

U2
P
=
(12V)2
6W
=24Ω，

通过它的电流是0.3A时灯泡的实际功率为：

P′=（I′）2R=（0.3A）2×24Ω=2.16W＜6W．

故选C．

阅读理解
阅读理解。
                             I
     The opening ceremony of this famous
yearly competition (比赛) will begin at
11:30 a.m. There will be music groups,
rappers and children's chorus. 12:25p.m.
sees the introduction of the eaters who
come from all over the world. At 12:40
p.m., the historic 12-minute all-you-can-
eat competition will begin.The world
record stands at over 50 hot dogs and
buns in 12 minutes. Will anyone beat the
record this year?
     Viewing is available on a first-come-
first-served basis. Television crews are
invited to use a two-tiered (两层) stage
three metres from the main stage. The
area in front of the main stage is kept
for photographers and television cameras
without tripods (三脚架). 		                                   II
     Few periods in history are as exciting as
the time when the Vikings (北欧海盗) were
known-and sometimes feared-throughout
Scandinavia, the British Isles, Russia, all the
Mediterranean, Africa and even America.
     Frojel is a family-based society, which
aims to relive and describe the Vikings from
a harbor-Frojel, on the Swedish island of
Gotland, Frojel was one of the richest trading
centers in the Viking world.
     The members of the society aim to recreate
the clothing, weapons, tools, jewellery, games,
food and furniture of that long-gone period.
They want to enjoy an escape to a simpler, more
relaxed time, with like-minded people. They will
also use the items they have made to relive that
age at various public entertainments.

1. According to Advertisement I, the famous yearly competition is _____.
A. a music competition
B. an eating competition
C. a cooking competition
D. a picture-taking competition
2. People who come to watch the competition earliest may _____.
A. get the best watching position
B. get the best food
C. watch whatever they want to
D. take good pictures
3. The best title for Advertisement II would be _____.
A. The Vikings
B. Reliving of the Vikings
C. Frojel
D. A Viking Reliving Society
4. From the advertisement we know that Frojel used to be _____.
A. a Viking club
B. a family-based society
C. a European island
D. a trading center
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多项选择题

要选择图案填充和相关联的边界，应设置PICKSTYLE的值为（）。

A.2

B.1

C.0

D.3
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