Answer:
2 a^2
Step-by-step explanation:
cube root of 8 = 2 cube root a^6 = a^2
We have two right triangles and three different rectangles.
The formula of an area of a right triangle:

l₁, l₂ - legs
We have l₁ = 20cm and l₂ = 21cm. Substitute:

The formula of an area of a rectangle:

l - length
w - width
We have:
rectangle #1: l = 22cm, w = 29cm

rectangle #2: l = 22cm, w = 21cm

rectangle #3: l = 22cm, w = 20cm

The total Surface Area of the triangular prism:

Answer:
B E F G
Step-by-step explanation:
Polygons are 2 dimensional shapes with straight edges (no curved edges). The shape needs to be closed up entirely to be a polygon. It cannot have any intersecting line segments
A can't be a polygon because the shape isn't closed up entirely
C can't be a polygon because it is a 3d shape
D can't be a polygon because it has curved edges.
H can't be a polygon because it isn't closed up (there are no line segments).
I can't be a polygon because polygons cannot have intersecting lines
J can't be a polygon because polygons cannot have intersecting lines
I hope this helps! If it does, a rate or brainliest would be much appreciated. :)