【判断题】当冷却系风扇正常工作时,气流应该吹向散热器。
【简答题】平面内的两条直线有相交和平行两种位置关系. (1)AB∥CD.如图a,由AB∥CD,有∠B=∠BOD,又因∠BOD是△POD的外角,故∠BOD=∠BPD +∠D,得∠BPD+∠D=∠B. 如图b,以上结论是否成立?若不成立,则∠BPD、∠B、∠D之间有何数量关系?请说明理由; (2)在图b中,将直线AB绕点B逆时针方向旋转一定角度交直线CD于点E,如图c,则∠BPD﹑∠B﹑∠D﹑∠BED之间有何数...
【简答题】平面内的两条直线有相交和平行两种位置关系。 (1)如图a,若AB∥CD,点P在AB、CD外部,则有∠B=∠BOD,又因∠BOD是△POD的外角,故∠BOD=∠BPD+∠D,得∠BPD=∠B-∠D,将点P移到AB、CD内部,如图b,以上结论是否成立?若成立,说明理由;若不成立,则∠BPD、∠B、∠D之间有何数量关系?请证明你的结论; (2)在图b中,将直线AB绕点B逆时针方向旋转一定角度交直线CD于...
【简答题】判断图中两直线的相对位置关系(平行、相交、交叉)。 _______ _______ _______ _______
【单选题】Tourist expenditures have different effects on a destination economy: sales by food vendors to restaurants are ______ effect; while taxi fares and fares and airline ticket sales are ______ effect.
【单选题】Other things the same, which of the following will raise the foreign exchange rate? An increase in
A.
the demand for home-issued securities by foreigners
B.
the foreign tourist expenditures in the home country
C.
the dividends received from abroad
D.
the domestic demand for foreign goods
【判断题】Maya 中的贴图文件不可以是 jpeg
【判断题】maya中的贴图文件不可以是jpeg。( )
【单选题】Invisible trade refers to:
A.
services that avoid tax payments
C.
legal, consulting, and engineering services
D.
tourist expenditures, only
【单选题】把两条直线的位置关系填入结构图中的M、N、E、F中,顺序较为恰当的是( ) ①平行 ②垂直 ③相交 ④斜交.