<PRE><B>Question 852153</B>
The formula for the surface area of a rectangular prism is 2ab + 2bc + 2ac = Surface Area.


We have 3 values:  18.5, 12, and 6.  We can assign each of these values a letter.  So, lets use a=6, b=18.5, and c=12.  Now, all we need to do is plug the values for each letter into our equation:


2(6)(18.5) + 2(18.5)(12) + 2(6)(12) = Surface Area. -----&gt;


222 + 444 + 144 = Surface Area -----&gt;


810 = Surface Area


So, the surface area of your prism is 810.</PRE>