... that for over a hundred years, the subject of the painting now identified as the Martyrdom of Saints
Crispin and Crispinian(close-up pictured) by Aert van den Bossche was a mystery?
... that
ants act as an intermediate host to complete the life cycle of the worm Raillietina tetragona, a parasite that infests in the intestines of birds such as chicken and pigeons?
The missing square puzzle is an
optical illusion used in mathematics classes to help students reason about geometrical figures. It depicts two arrangements of shapes, each of which apparently forms a 13×5
right-angled triangle, but one of which has a 1×1 hole in it.
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