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Evaluate the following:
$67^2$
$667^2$
$6667^2$
$66667^2$
Sixty-seven Squared
Age 16 to 18
Challenge Level 
Evaluate the following:
$67^2$
$667^2$
$6667^2$
$66667^2$
What do you notice?
Can you convince someone what the answer would be to (a million sixes followed by a 7) 2 ?
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