违反法律和国家政策、计划的合同，在经济合同中视为（）合同。A．失效 B．无效

第二次鸦片战争前后，吞并我国北方150多万平方千米的侵略者是（   ）

A．英国

B．法国

C．日本

D．沙俄

指出关于主启动阀的错误论述（）。

A．满足启动时所需要的压缩空气量

B．减少压缩空气的节流损失

C．控制启动定时和发火顺序

D．它是压缩空气系统的总开关

理财金账户销户后，客户（）

A、不能再开“理财金账户”

B、不得再享受“理财金账户”的各种优惠待遇

C、不再是我行的优质客户

D、仍可享受“理财金账户”的各种优惠待遇

患者，男，45岁，一周前因急性阑尾炎，进行手术治疗时，阑尾系膜出血，缝扎止血时致回肠末段血运障碍，行回肠部分切除吻合术，腹腔引流，间断性引出血性液每日约200ml，查体：腹胀，右侧腹压痛，未触及肿块，肠鸣音弱，BP16/11kPa，P20次/分，白细胞，12×10⁹/L中性80%。应采取主要措施

A．剖腹探查

B．支持疗法

C．腹腔灌洗

D．肠造口术

E．以上均不是

Exercising to music pumps up brain power

If music makes you smarter, and exercise helps brain function, can exercising to music really boost brainpower Some researchers said it can. Volunteers who listened to Vivaldi’s "Four Seasons" while working out on a treadmill did much better on a test of (1) ability than when they exercised without music, a team (2) Ohio State University found.
"Evidence suggests that exercise improves the (3) performance of people with coronary artery (4) ," said psychologist Charles Emery, who led the study.
"And listening to music is (5) to enhance brainpower. We wanted to put the two results together," Emery (6) in a statement.
Writing in the latest issue of the journal Heart & Lung, Emery and (7) said they studied 33 men and women taking (8) in a cardiac rehabilitation program after having bypass (9) , angioplasty or other procedures to treat clogged arteries.
The (10) said they felt better emotionally and mentally after working out (11) or without the music. But their improvement on the (12) fluency test doubled after listening to music on the treadmills.
"Exercise seems to (13) positive changes in the nervous system, and these changes may have a (14) effect on cognitive ability," Emery said.
"Listening to music may (15) cognitive function through different pathways in the brain. The combination of music (16) exercise may stimulate and increase cognitive arousal (17) helping to organize cognitive output."
Emery said he now wanted to (18) people using music of their own choice. "We used the ’Four Seasons’ because of its (19) tempo and positive effects on medical patients in previous (20) ," Emery said. "But given the range of music preferences among patients, it’s especially important to evaluate the influence of other types of music on cognitive outcomes.\