Don’t Count on Dung (粪) Conservationists (自然保护主义者) may be miscalculating the numbers of the threatened animals such as elephants, say African and American researchers. The error occurs because of a flaw in the way they estimate animal numbers from the piles of dung the creatures leave behind. The mistake could lead researchers to think that there are twice as many elephants as there really are in some regions according to Andrew Plumptre of the Wildlife Conservation Society (WCS) in New York. Biologist Katy Payne of Comell University in Ithaca, New York, agrees, "We really need to know elephant numbers and the evidence that we have is quite indirect, " says Payne, who electronically tracks elephants. Counting elephants from planes is impossible in the vast rainforests of Central Africa. So researchers often estimate elephant numbers by counting dung piles in a given area. They also need to know the rate at which dung decays because it’s extremely difficult to determine these rates. However, researchers counting elephants in one region tend to rely on standard decay rates established elsewhere. But researchers at the WCS have found that this decay rate varies from region to region depending on the climate and environment. Using the wrong values can lead the census astray (离开正道), says Plumptre. He and his colleague Anthony Chifu Nchanji studied decaying elephant dung in the forests of Cameroon. They found that the dung decayed between 55 and 65 per cent more slowly than the dung in the rainforests of neighboring Gabon. If researchers use decay rates from Gabon to count elephants in Cameroon, they would probably find more elephants than are actually around. This could mean estimates in Cameroon are at least twice as high as those derived from decay rates calculated locally, Plumptre says, "However accurate your dung density estimate might be, the decay rate can severely affect the result". Plumptre also says that the dung-pile census should be carried out over a region similar in size to an elephant’s natural range. The usual technique of monitoring only small, protected areas distorts numbers because elephants move in and out of these regions, he says, "If the elephant population increases within the protected area, you can not determine whether. It is a real increase or whether it is due to elephants moving in because they are being poached (入侵偷猎) outside." Plumptre says that similar problems may also affect other animal census studies that rely on indirect evidence such as nests, tracks or burrows (地洞).Piles of dung can’t be relied upon when it comes to estimating elephant numbers because _____

单击（）按钮可以创建对象。

A:Create B:Plane C:Scatter D:New

制作不规则散布的物体，一般使用符合对象中的（）。

A:Morph B:Scatter C:Conform D:BlobMesh

某系统Oracle数据库中的AWR报告中产生大量的db scatter read waits等待事件，那么最有可能产生该等待事件的操作是（）。

A:大量的insert操作 B:大量索引扫描 C:大量全表扫描 D:大量的update操作

The defeated troops were ordered to scatter and then concentrate fifty miles to the south.

A:rally B:attack C:march D:retreat

The defeated troops were ordered to scatter and then {{U}}concentrate{{/U}} fifty miles to the south.

A:rally B:attack C:march D:retreat

SCATTER命令用于将当前记录的各字段值送到一个数组中，与该命令相对应的、利用数组更新当前记录字段值的命令是______。

A:GATHER B:UPDATE C:REPLACE D:CHANGE

把当前表当前记录的学号，姓名字段值复制到数组A的命令是：
SCATTER FIELD学号，姓名______。

把当前表当前记录的学号，姓名字段值复制到数组A的命令是
SCATTER FIELD学号，姓名【13】。

把当前表当前记录的学号，姓名字段值复制到数组A的命令是 SCATTER FIELD学号，姓名【13】。

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