PROBLEMS AND SOLUTIONS.

The article proposes several mathematical problems and offers solutions to these mathematical problems. Marius Stefan of Los Angeles, California provides solution to the mathematical problem which was proposed by Chu Cheng of China. Pal Peter Dalyay of Hungary solves the proposed triangle inequality problem which was cited by Wu Wei Chao of China. Richard Ston of Texas solves the greatest lower bound problem which was proposed by Michel Bataille of France. Victor Pambuccian's paper "Positive definitions of segment congruence in terms of segment inequality" provides a solution to the reverse engineering problem which was proposed by Bogdan Nica of Tennessee.