填空题：焊接缺陷按其在焊接接头的部位，可分为（）和（）。

题型：选择题

如图所示，以8m/s匀速行驶的汽车即将通过路口，绿灯还有2s将熄灭，此时汽车距离停车线18m．该车加速时最大加速度大小为2m/s²，减速时最大加速度大小为5m/s²．此路段允许行驶的最大速度为12.5m/s，下列说法中正确的有（　　）

A．如果距停车线5m处减速，汽车能停在停车线处

B．如果立即做匀减速运动，在绿灯熄灭前汽车一定不能通过停车线

C．如果立即做匀加速运动，在绿灯熄灭前通过停车线汽车一定超速

D．如果立即做匀加速运动，在绿灯熄灭前汽车不能通过停车线

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题型：多项选择题

感染性心内膜炎栓塞症状有（）

A.脾大

B.肝大

C.腹痛

D.胸痛

E.便血、血尿

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题型：填空题

(8分)某芳香烃中含碳元素的质量分数为90.6%，相同条件下，其蒸气密度为空气密度的3.66倍(M_空气设为29)。

(1)该烃的分子式为__________。其最简单的同系物中能使酸性高锰酸钾溶液褪色的是(写出其结构简式)__________________。

(2)若该烃硝化时，苯环上的一硝基取代物有三种，则该烃的结构简式可能为____________________。

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题型：选择题

反应N₂O₄(g) 2NO₂(g)　ΔH＝＋57 kJ·mol^－1，在温度为T₁、T₂时，平衡体系中NO₂的体积分数随压强的变化曲线如图所示。下列说法正确的是 (　　)

A．a、c两点的反应速率：a>c

B．a、c两点气体的颜色：a深，c浅

C．b、c两点的平衡常数：b<c

D．a、c两点气体的平均相对分子质量：a>c

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题型：单项选择题

With stripes of blue ink snaking across his face and neck and then disappearing under the collar of his shirt before bursting into the open from under the cuffs, he is a poster boy for his profession.
Skitch, the only name he wants the public to know, exhibits pride and confidence in his designer skin.
Comfortably perched atop a stool in Graffixx Tattoo, a parlor just two blocks from the White House, he talks about his obsession with" body art", which, in his view, is winning the souls of the New Age generation as well as overall public acceptance.
"It’s definitely more popular than when I started out about 10 years ago," he said as a flash of sunshine danced on a big pin piercing the skin between his eyes. "People who wouldn’t even think about having a tattoo then have them.
There are no official statistics beating Skitch out. But evidence that tattoos are growing more popular is abundant on beaches, in health clubs and on the streets when summertime clothes reveal roses, mermaids and increasingly more sophisticated ornaments on shoulders, ankles and other body parts.
As far as Skitch is concerned, he is tiding the wave of the future.
The revenue of a tattoo parlor he co-owned in Minneapolis, Minnesota between 1997 and 1999 grew 60 percent in its second year of operation, he said.
"We would have made even more, if we operated in some southern resort towns, like Orlando; Daytona Beach or in southern California," he said.
It is woman, he said, who is increasing numbers driving the body art boom. "If ten years ago only 40 percent of our clients requiring tattoos were women, now they make up 50 percent," notes Skitch. "For body piercing, it’s 80 percent."
Not so long ago, tattoo parlors were found in back rooms of seedy port city bars and catered to visiting sailors and city toughs.
Not anymore. Next month, top female tattoo artists from North America and Europe will descend on Orlando, Florida, for a four-day convention, according to an announcement posted on the Internet by Deana Lippens, the organizer.
Tattoos themselves have dramatically evolved over the years, becoming more complex, multi-dimensional, even exquisite, say tattoo artists.
They are no longer just model rosettes hidden on a shoulder blade. Bodies are being transformed into full-scaled tableaux featuring, for example, portraits of saints adorned by garlands of flowers or a bald eagle spreading his wings across a human torso. Some of these tableaux take years to complete.

According to the passage, which of the following statements is true

A．Now there are fewer men fond of body art than before.

B．The official statistics proved that body art gains popularity.

C．All people who didn’t think about having a tattoo then now have them.

D．Skitch started to engage in body art about ten years ago.

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焊接缺陷按其在焊接接头的部位，可分为（）和（）。

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