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【简答题】
新域广场省政府办公楼前，五星红旗在空中飘扬，同学们为了测出旗杆的高度，设计了三种方案， 方案一：在地上放一块平面镜，使人能在镜中刚好能看到旗杆顶．如图（1），测得BO=60米；OD=3.4米，CD=1.7米； 方案二：在晴天观测人和旗杆的影子，如图（2），测得CD=1米，FD=0.6米，EB=18米； 方案三：伸直手臂，在手中竖直拿一刻度尺，眼睛通过刻度尺观测旗杆顶端和旗杆底端，如图（3）所示，并测得BD=90米，EG=0.2米，此人的臂长为0.6米．请你任选其中的一种方案． （1）其运用的物理知识为光是直线传播的． （2）利用同学们实测的数据，旗杆的高度为( )米．
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【多选题】Which three tasks can be performed by using the performance Schema?（）
A.
Finding queries that are not using indexes
B.
Finding rows that are locked by InnoDB
C.
Finding client connection attributes
D.
Finding the part of a code in which a single query is spending time
E.
Finding the size of each table
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【单选题】In order for a vessel to be engaged in fishing she must be ().
A.
underway
B.
using gear which extends more than 50 meters outboard
C.
using a seine of some type
D.
using gear which restricts her maneuverability
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Using media is always necessary.
B.
Using media will have bad effect sometimes.
C.
A good presentation do not need to use media.
D.
Using media that you are not familiar with can help you.
【单选题】● Which of the following can be tracked using the WBS?
A.
time
B.
cost
C.
performance
D.
scope
E.
None of the above.
【单选题】____________________ engaged in the sale of products using marketing methods which do not include a physical location.
A.
Store retailers
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Non-store retailers
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Brick-and mortar store retailer
D.
Traditional store retailers
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