使用combiner的原因是（）

A:最多可以有4个Site使用同一PCM链路 B:多个TRXs可以使用同一天线系统 C:手机可以同进收听2个基站的信息 D:发射和传送均由同一天线完成

COMBINER（组合器）分哪两类？

关于华为交换机设备中的Hybrid端口下面说法正确的是：（）

A:Hybrid端口只能用来连接网络设备 B:Hybrid端口只能用来连接主机 C:Hybrid端口既可以用来连接主机，又可以用来连接网络设备 D:Hybrid端口上不能配置默认VLAN

下列关于华为交换设备中Hybrid端口说法正确的是：（）

A:Hybrid端口可以灵活的控制VLAN标签的移除情况。 B:对于从Hybrid端口接收到的不带Tag的帧，交换机不会在帧中加上Tag标记。 C:如果某Hybrid端口的taggedVLAN是none，而untaggedVLAN只有一个取值，则该端口与access端口功能相同。 D:如果某Hybrid端口没有配置untaggedVLAN，则与trunk端口功能相同。

下列关于华为交换设备中Hybrid端口说法错误的是（）

A:Hybrid端口是交换机上既可以连接用户主机，又可以连接其他交换机的端口 B:Hybrid端口既可以连接接入链路又可以连接干道链路 C:很多型号的华为交换机默认端口类型是Hybrid，PVID默认是1，VLAN1由系统创建，可以删除 D:Hybrid端口允许多个VLAN的帧通过，并可以在出端口方向将某些VLAN帧的Tag剥掉

以下哪一项有关CDU的叙述是正确的？（）

A:CDU－C＋只可以部分兼容CDU－C的功能 B:CDU-A可以和CDU-C混合使用 C:CDU－A内部包括了Hybrid Combiner D:CDU－C内部没有Hybrid Combiner

采用滤波型合成器（Filter COMBINER）的CDU类型是（）。

A:G型CDU B:F型CDU C:C+型CDU D:D型CDU

Jim Boon is a hybrid kind of guy. He drives a Toyota hybrid to work, a Honda hybrid on weekends and, as a manager for Seattle public transit he recently placed the world’s largest order for hybrid electric buses.
Now, with the biggest hybrid-bus fleet in the world, Seattle has become the main testing ground for a technology that claims it can drastically cut air pollution and fuel consumption. In the 1990s, demo fleets of 35 buses or fewer started cropping up in cities such as Tempe, Ariz. Sixteen of these early hybrids still service Genoa, Italy, where drivers switch from diesel to electric power when passing the city’s downtown architectural treasures. But no city has gone as far as Seattle, which last year bought 235 GM hybrid buses at $ 645,000 a pop. When the final one rolls out this December, the region’s bus system will be 15 percent hybrid.
But why Seattle, and why now The Pacific Northwest has long been a hotbed of both Green politics and cutting-edge technology. Fourteen years ago the Seattle area bought 236 Italian-made Breda buses to service a mile-long downtown tunnel. They were supposed to operate as clean electric trolleys underground, but the switching mechanism often failed and "the bus drove through the tunnel as a diesel," says Boon. "It was pretty loud and smoky. "
When the Bredas hit retirement age in 2002, Boon went shopping. He chose the GM buses because they use an automatic transmission and diesel boosters that provide power to scale inclines without strain. In hilly Seattle, the prospect of a hybrid that could climb like a diesel but accelerate without belching black fumes helped justify a price $ 200,000 higher than that of a regular bus. "The days of seeing a diesel pull away and pour out smoke are over," says Boon. "After we drove these hybrid buses across the country, I wiped a handkerchief inside the tailpipe. It came out spotless. "
Experts say buses are critical to realizing the hybrid dream of greater efficiency and cleaner air. It would take thousands of hybrid cars to save as many gallons of gas (750,000) as Boon expects his buses to save Seattle each year. GM claims that compared with conventional diesels, its new buses also churn out 90 percent less particulate matter—a known carcinogen. "Buses are a major source of pollution in any city," says Dave Kircher of the Puget Sound Clean Air Agency. "They operate where people are breathing this exhaust, so this is a major step forward in terms of emissions. "
And a major step forward in the marketplace: Philadelphia, Honolulu, Long Beach, Calif., and Albuquerque, N. M. , have all bought the GM buses in recent months. GM is now touting itself in ads as the top hybrid-bus innovator, but Siemens is among the global giants dueling GM for new business, and New York plans to deploy 325 BAE Systems hybrids by 2006. "There’s room for competition," says James Cannon, editor of Hybrid Vehicles newsletter. Seems Seattle isn’t the only city trying to leave grunge behind.
Which of the following is true according to the text

A:Many cities plan to buy GM buses. B:GM buses have the incomparable advantages over other buses. C:There is severe competition in the field of hybrid vehicles. D:The best way to keep the city clean is to buy hybrid buses.

Jim Boon is a hybrid kind of guy. He drives a Toyota hybrid to work, a Honda hybrid on weekends and, as a manager for Seattle public transit he recently placed the world’s largest order for hybrid electric buses.
Now, with the biggest hybrid-bus fleet in the world, Seattle has become the main testing ground for a technology that claims it can drastically cut air pollution and fuel consumption. In the 1990s, demo fleets of 35 buses or fewer started cropping up in cities such as Tempe, Ariz. Sixteen of these early hybrids still service Genoa, Italy, where drivers switch from diesel to electric power when passing the city’s downtown architectural treasures. But no city has gone as far as Seattle, which last year bought 235 GM hybrid buses at $ 645,000 a pop. When the final one rolls out this December, the region’s bus system will be 15 percent hybrid.
But why Seattle, and why now The Pacific Northwest has long been a hotbed of both Green politics and cutting-edge technology. Fourteen years ago the Seattle area bought 236 Italian-made Breda buses to service a mile-long downtown tunnel. They were supposed to operate as clean electric trolleys underground, but the switching mechanism often failed and "the bus drove through the tunnel as a diesel," says Boon. "It was pretty loud and smoky. "
When the Bredas hit retirement age in 2002, Boon went shopping. He chose the GM buses because they use an automatic transmission and diesel boosters that provide power to scale inclines without strain. In hilly Seattle, the prospect of a hybrid that could climb like a diesel but accelerate without belching black fumes helped justify a price $ 200,000 higher than that of a regular bus. "The days of seeing a diesel pull away and pour out smoke are over," says Boon. "After we drove these hybrid buses across the country, I wiped a handkerchief inside the tailpipe. It came out spotless. "
Experts say buses are critical to realizing the hybrid dream of greater efficiency and cleaner air. It would take thousands of hybrid cars to save as many gallons of gas (750,000) as Boon expects his buses to save Seattle each year. GM claims that compared with conventional diesels, its new buses also churn out 90 percent less particulate matter—a known carcinogen. "Buses are a major source of pollution in any city," says Dave Kircher of the Puget Sound Clean Air Agency. "They operate where people are breathing this exhaust, so this is a major step forward in terms of emissions. "
And a major step forward in the marketplace: Philadelphia, Honolulu, Long Beach, Calif., and Albuquerque, N. M. , have all bought the GM buses in recent months. GM is now touting itself in ads as the top hybrid-bus innovator, but Siemens is among the global giants dueling GM for new business, and New York plans to deploy 325 BAE Systems hybrids by 2006. "There’s room for competition," says James Cannon, editor of Hybrid Vehicles newsletter. Seems Seattle isn’t the only city trying to leave grunge behind.

A:Many cities plan to buy GM buses B:GM buses have the incomparable advantages over other buses C:There is severe competition in the field of hybrid vehicles D:The best way to keep the city clean is to buy hybrid buses