7.Axes 2 and 3 intersect,
 3 and 4 are parallel.


9.Axes 1 and 2 intersect,
 3 and 4 intersect.


8.Axes 1, 2, and 3 intersect.


10.Axes 2 and 3 intersect,
 3 and 4 intersect.


Figure 5.1--Continued.-

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