gaokao 2019 Q8

gaokao · China · national-III-arts Vectors 3D & Lines MCQ: Relationship Between Two Lines
8. As shown in the figure, point $N$ is the center of square $A B C D$ , $\triangle E C D$ is an equilateral triangle, plane $E C D \perp$ plane $A B C D$ , and $M$ is the midpoint of segment $E D$ . Then [Figure]
A. $B M = E N$ , and lines $B M$ and $E N$ are intersecting lines
B. $B M \neq E N$ , and lines $B M$ and $E N$ are intersecting lines
C. $B M = E N$ , and lines $B M$ and $E N$ are skew lines
D. $B M \neq E N$ , and lines $B M$ and $E N$ are skew lines
The figure on the right is a flowchart for computing $\frac { 1 } { 2 + \frac { 1 } { 2 + \frac { 1 } { 2 } } }$. The blank box in the figure should contain
8. As shown in the figure, point $N$ is the center of square $A B C D$ , $\triangle E C D$ is an equilateral triangle, plane $E C D \perp$ plane $A B C D$ , and $M$ is the midpoint of segment $E D$ . Then\\
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A. $B M = E N$ , and lines $B M$ and $E N$ are intersecting lines\\
B. $B M \neq E N$ , and lines $B M$ and $E N$ are intersecting lines\\
C. $B M = E N$ , and lines $B M$ and $E N$ are skew lines\\
D. $B M \neq E N$ , and lines $B M$ and $E N$ are skew lines\\