Try out this website or search "surface area of a triangular prism" in Google
http://www.ck12.org/geometry/Surface-Area-of-Triangular-Prisms/lesson/Surface-Area-of-Triangular-Pri...
The null hypothesis is often used as a statement <span>about the population the researcher suspects is true and is trying to find evidence for in formulating a statistical test of significance. In addition to that, it is commonly used when stating that there is no significant difference between subjects.</span>