Prisms are 3-D polyedra with parallel, congruent bases.

The surface area of a prism is the total area of its faces.
If we break this prism into its parts we are going to have 2 bases (hexagons) and 6 lateral faces (rectangles) which make up the lateal area.

It is pretty easy to calculate their areas and then add them up.
Find the surface area
of the triangular prism in cm2

Solution:
SA=2·Atriangle+2·Arectangles+Abase
Atriangle=
= 100
Arectangle=
Abase= 50·20=1000
SA= 

cm2