桐油(未经化学改性)

下图为某石灰岩地区不同植被下土壤空气中CO2浓度示意图，完成1—2题。

1、如果水分条件相同，那么图中哪种植被下的土壤、岩石最易被溶蚀[ ]

A、无植被耕地

B、人工草坡

C、柏树林

D、天然草坡

2、关于该地区的叙述，错误的是[ ]

A、交通建设时施工困难，主要是由于降水较多

B、交通建设时施工困难，主要是由于喀斯特地貌广布，地表破碎

C、发展农业要注意保护植被，防止水土流失

D、该地地表水缺乏与容易渗漏密切相关

奥斯特洛夫斯基说：“谁若与集体脱离，谁的命运就要悲哀。”对此，下列认识正确的是

A．人的命运是由集体决定的

B．个人是组成集体的细胞

C．集体不论大小，团结才是力量

D．个人离不开集体

赵某向李某借款10万元，赵某将自己的汽车作价5万元抵押给李某，未约定担保数额，并依法进行了登记。后一次事故使汽车报废，保险公司赔偿8万元。赵某与李某之间的抵押关系怎样

A．应归于消灭

B．继续有效，应以保险赔偿金中的5万元继续担保赵某对李某的债务

C．继续有效，应以全部保险赔偿金8万元继续担保赵某对李某的债务

D．终止，赵某应以保险赔偿金提前清偿李某

通常，在订有自动垫缴保险费条款的长期人寿保险合同中，自动垫缴保费条款生效的前提条件是（）

A.必须经保单持有人同意

B.必须经被保险人同意

C.必须经受益人同意

D.必须经代理人同意

Until recently, mobile radio was to wireless communications what the Yugo was to transportation. With a mixed clientele ranging from truckers using CBs to police armed with walkie-talkies to taxi drivers dispatched by radio, it was viewed as an unglamorous business and a technological backwater.

But specialized mobile radio, as it is known, has been rediscovered. It is now considered one of the biggest prizes in the all-out war for the public airwaves. The reason: high-tech companies have figured out how to profitably rebuild the antiquated dispatching system into an advanced cellular-telephone network that can take on the likes of AT & T and the giant Baby Bells. Upstart Nextel Communications sent shock waves through the industry last week when it agreed to buy Motorola’s SMR frequencies for $1.8 billion.

That could pose a serious threat to cellular hegemony. Although both systems are based on the same basic technology, SMR systems are digital and cover almost 25 times as much area as the average cellular network. SMR handsets won’t work on cellular systems and tend to be bulkier than cellular phones, though they provide more features, like a digital pager service. And while cellular growth has tripled to some 13 million subscribers since 2000, the technology has been losing ground. It is running out of channel capacity so fast, in fact, that 40% of cellular calls in high-density areas like Manhattan and Los Angeles fail to be completed. SMRs have capacity to spare, and service could eventually be priced 10% to 15% less than cellular. Dispatchers predict they will have at least 10 million subscribers by the end of the decade. There are now about 1.5 million users of SMRs.

The addition of another contender to an already crowded field of telephone systems will surely multiply the confusion. By the year 2010, consumers will be able to choose from at least half a dozen vendors of a dizzying array of wireless-communications services, including pagers, voice mail answering machines and cellular phones. Phone and cable television operators, such as Bell South, MCI and Cox Enterprises, are developing so-called personal communications networks, or PCNs, a highly advanced portable-phone system that is expected to cover a wider area, connect to a greater variety of services and be cheaper to operate than conventional cellular.

And many companies that have gambled on the wrong technological standards, and invested billions trying to develop the same markets, will undoubtedly lose a great deal of money before the shakeout is over. "The winners," says Nextel chairman Morgan O’Brien, "will be those who can make the choice for consumers easy." With all the anticipated confusion--mindful of the early years of personal computers--it is likely to be years before anyone calls the purchase of wireless products an "easy" choice.

We learn from the text that users of wireless products are more often than not confronted with（）

A. missing networks

B. technical failures

C. wrong standards

D. confusing choices