Answer:
⚪ 4: three right triangles and one acute-angled triangle.
Step-by-step explanation:

Answer:
equilateral equiangular, or the third one
Step-by-step explanation:
Acute and obtuse is describing an angle of a certain triangle to describe what kind of a triangle it is.
Isosceles right is a type of a triangle.
So, equilateral equiangular is the only thing left.
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