在同一地点用相等的初速度v0=50m/s，先后竖直向上抛出两块小石块，第二块比第

如图所示电路，使灯L₁、L₂串联，应闭合开关_________ ，断开开关 _________ ；要使L₁、L₂并联，应闭合开关_________ ，断开开关_________ ；如果闭合S₁、S₃，断开S₂，灯_________ 亮；如果闭合开关 _________ 会出现短路，这绝不允许．

建设工程组织流水施工时，相邻专业工作队之间的流水步距相等，且施工段之间没有空闲时间的是( )。

A．非节奏流水施工和加快的成倍节拍流水施工

B．一般的成倍节拍流水施工和非节奏流水施工

C．固定节拍流水施工和加快的成倍节拍流水施工

D．一般的成倍节拍流水施工和固定节拍流水施工

______ sunshine and rainfall ______ a good harvest of fruits and begetables this year.

A．A large quantity of ; promise

B．A large number of; promise http:/

C．A large quantity of; promises

D．Large quantities of; promises

A device that stops drivers from falling asleep at the wheel is about to undergo testing at Department of Transport laboratories and could go on sale within 12 months.

The system, called Driver Alert, aims to reduce deadly road accidents by 20% - 40% that are caused by tiredness. Airline pilots can also use it to reduce the 30% of all pilot-error accidents that are related to fatigue.

Driver Alert is based on a computerized wristband. The device, worn by drivers or pilots, gives out a sound about every four minutes during a car journey. After each sound the driver must respond by squeezing the steering wheel. A sensor in the wristband detects this pressing action and measures the time between the sound the driver’s response.

Tiredness is directly related to a driver’s response time. Usually, a watchful driver would take about 400 milliseconds to respond, but once that falls to more than 500 milliseconds, it suggests that the driver is getting sleepy.

In such cases the device gives out more regular and louder sounds, showing that the driver should open a window or stop for a rest. If the driver’s response continues to slow down, the sounds become more frequent until a nonstop alarm warns that the driver must stop as soon as possible.

The device has been delivered to the department’s laboratories for testing. If these tests, scheduled for six months’ time, are successful, the makers will bring the product to market within about a year.

小题1:According to the text, Driver Alert ______.

A．aims to reduce tiredness-related accidents

B．has gone through testing at laboratories

C．aims to prevent drivers from sleeping

D．has been on sale for 12 months小题2:How should a driver respond to the sounds from Driver Alert?

A．By sounding a warning.

B．By touching the wristband.

C．By checking the driving time.

D．By pressing the steering wheel.小题3:We can learn form the text that the driver needs to stop for a break when his response time is ______.

A．about 400 milliseconds

B．below 500 milliseconds

C．over 500 milliseconds

D．about 4 minutes小题4:When the driver gets sleepy while driving, Driver Alert ______.

A．moves more regularly

B．stops working properly

C．opens the window for the driver

D．sounds more frequently and loudly

为期货公司提供中间介绍业务的机构的期货从业人员需要收付、存取或者划转期货保证金。 ( )