【单选题】以下命题: ①若m?α,l?α,l与m不相交,则l ∥ α; ②若b?α,c?α,l?α且b、c相交,l与b、c不相交,则l ∥ α; ③若b ∥ c,b ∥ α,则c ∥ α; ④若l ∥ α,b ∥ α,则l ∥ b. 其中是真命题的个数为( )
【简答题】Preview Chapter 5 of your textbook and Chapter 3 of 《 学术 》 the PPT of next class and answer the following questions by your own PPT. l 1. How to review/read literature? l 2. How to t ak e n otes ? l 3...
【简答题】______ is a kind of clean L/C. It is also called commercial paper L/C, or guarantee L/C , or performance L/C.
【单选题】砂子的表观密度为 ρ,堆积密度为ρ l ,紧密密度为 ρ c ,则存在下列关系( ) A ρ >ρ l > ρ c B ρ c > ρ>ρ l C ρ>ρ c > ρ l D ρ l > ρ>ρ c
【多选题】在Windows2008R2系统DNS服务器里,可以创建下列的哪些资源与记录( )。