在Windows中，下面关于对话框的叙述正确的是____。A．对话框可以最大化 B．

甲基红试验中培养基的pH需降至多少，指示剂才指示阳性结果()

A．2.5

B．5.O

C．4.5

D．6.5

E．7.4

一块完整的骨属于组织．______．

下列现象与空气中的什么成份有关：

（1）饼干在空气中放置久了会变软______；

（2）澄清的石灰水敞口放置会变浑浊______；

（3）燃烧和呼吸______；

（4）“霓虹灯”通电后发出五颜六色的光______；

（5）食品包装袋内会充入______防腐．

People playing computer games to train their brains might as well be playing Super Mario, a new research suggests. In a six-week study, experts found people who played online games designed to improve their cognitive skills didn’t get any smarter．

Researchers recruited（招募） participants from views of the BBC’s science show Bang Goes the Theory．More than 8,600 people aged 18 to 60 were asked to play online brain games designed by the researchers to improve their memory, reasoning and other skills, for at least 10 minutes a day, three times a week．

小题1:What’s the purpose of online brain games according to the designers?

A．To take part in the study.

B．To draw public attention to computer.

C．To provide free service to teenagers.

D．To improve players’ IQ.小题2:How many people were inveolved in the study made by the researchers?

A．About 60.

B．Only 2700.

C．8600 or so.

D．Around 11,300.小题3:．What’s the result of the study about online games?

A．Those who didn’t play online games felt disappointed.

B．Those who played online games proved smarter.

C．Online games don’t improve the players’ skills at all.

D．Online games will be more popular than before.小题4:The best title for the passage may probably be         .

A．Don’t Play Games Any More

B．New Study of IQ

C．Brain Games Don’t Raise IQ

D．Brain Games and Super Mario

教学既是科学，又是（）。