Question

1. Consider an interpretation where "points" are the numbers 1,2,3 and 4, "lines" are the sets {1,2}, {1,3}, {1,4}, and {2,3, 4}, and “lies on" means "is contained in." (b)

(6 pts) Which (if any) parallel postulate does this interpretation satisfy? Prove your answer. (a) (8 pts) Is this a model for incidence geometry? Prove your answer. (c) (4 pts) Is this a model for neutral geometry? Prove your answer.

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