Answer:
A parallelogram
Step-by-step explanation:
One of the definitions of a parallelogram is that opposite sides are equal. In this case, 6 = 6 and 4 = 4 so it is a parallelogram.
On the other hand, if you are talking about the shapes making up the parallelogram, they are triangles because they have 3 sides.

so.... since the number after .81 is 1, it doesn't really round up to .82, so is just that, 15.81.
Answer:
540
Step-by-step explanation:
The easiest way to do this is to:
Find the surface area of ONE cube minus a side
6*6= 36*5 = 180
Then multiply it by THREE to find the total surface area:
180*3 = 540