Positional properties

2000006511

Level: 
B
Let ABCDV be a rectangle based-pyramid, where V is its apex and K, M are the midpoints of its edges AD, BV respectively. What is the cross-section of the pyramid if we slice it with a plane KCM?
a quadrilateral KCMP with point P lying on the edge AV
a triangle KCM
a quadrilateral KCMP with point P lying on the edge DV
a quadrilateral KCMP with point P lying on the median KV if the triangle ADV

2000006512

Level: 
B
Let ABCDV be a rectangle based-pyramid, where V is its apex and L, N are the midpoints of its edges BC, CV respectively. What is the cross-section of the pyramid if we slice it with a plane ALN?
a quadrilateral ALNR with point R lying on the edge DV
a triangle ALN
a quadrilateral ALNR with point R lying on the edge AV
a quadrilateral ALNR with point R lying on the edge BV