Ican't find the surface area, is this confusing me.

Find the area of two sides (Length*Height)*2 sidesFind the area of adjacent sides (Width*Height)*2 sidesFind the area of ends (Length*Width)*2 endsAdd the three areas together to find the surface area

Length times height to find a square or rectangle and / or square

To find triangle its length times night divided by 2

6•20
+
8•20
+
20•10
+
In this case you can multiply 8 times 6 only once Because there is another triangle exactly the same

120 + 160 + 200 + 48

Answer- 528

Ithink it's the first one ( let me know if it right)