Answer:
Second one.
Explanation:
A right triangle is a triangle with one right angle. A right angle can be shown with a box, we see that in 1, 3, and 4, there is a box, so that means 2 is not a right angle. We can also do out the math for number 2, so 67+67 = 134, and 180 - 134 is not 90.
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