Sentence 1: If a surface has a constant zero developable curvature , it is an Euclidean surface and the geometry of the surface is a Gaussian geometry .
Sentence 2: When a surface has a constant zero developable curvature , then it is a Euclidean surface and the geometry of the surface is Gaussian geometry .
Question: Do Sentence 1 and Sentence 2 express the same meaning? Yes or No?