3 Let A be an ordered plane (i. e. a model of I1-I3, B1-B4). Let A, B, C be three non-collinear
points of A. Prove that there exists a line which intersects the three lines AB, BC, and CA in
three different points M, N, and P, respectively, such that A*B*M, B*C*N, and A*C* P hold.