| Part 1: See:
We found the most important information is that we must find
out all the shapes that the pieces can be if the pieces are the same
size.
Plan: We decide to find all the
shapes that the pieces can be from a basis one.
Do: Because the hexagon is cut
into 54 pieces so every piece we should found is made by 6 pieces.
We begin with a hexagon, made like this:
Then we pick out the triangle in the shadow and put it into area 1,2
or 3, we can get 3 shapes:

If we pick out two triangles and put them in different place we can
get:

If we pick out three triangles and put them in different place we can
get:

So we have 1(the basis one)+3+7+1=12 shapes.
Part 2: See:
we find the most important information is: the pieces are used to cover
the hexagon by eight different-shaped pieces with one piece being
repeated to make nine pieces in all.
Plan: We decide to use all the
shapes we found to do this problem.
Do: We try to find out all the
answers and we have (the red two are repeated ones):

Check: We check our answers
carefully we think we find all the answers.
When we aggregated all the solutions sent in, we found that we had
received 26 different arrangements. Also, some teams discovered
that you don't actually need to repeat one of the pieces. As the Wolfram
site explains, there are at least 15 different ways of tiling this
T-hexagon with different hexiamonds. And there seem to be two ways of
tiling it with just one hexiamond:
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