Please, help I don't understand vectors T.T

Question

1. In the prism, assume all dimensions have different lengths, state the following:

a) state 3 equal vectors to DC⃗

b) state 4 opposite vectors to BC⃗
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Here is the prism below,

imgur dot com/pMNbX

Answer 1

I can only assume that while the perpendicular lengths are all different, the faces are parallel?

In that case
AB=DC=EF=HG

opposite to BC would be equal to CB:
CB=DA=HE=GF

since these are vectors, and not just edge lengths, you need to be sure to indicate the direction correctly.