Answer: See the diagram below
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Explanation:
The base is always perpendicular to the height, meaning the two form a 90 degree angle (aka right angle).
In column 1, refer to the figures as 1, 2 and 3 (working top to bottom).
In column 2, refer to the figures as A, B, C
Figure 1 matches with figure B
Figure 2 matches with figure C
Figure 3 matches with figure A.
These matches are of course the base with the proper height.
