Right Triangles in a Square

1. Find the smallest square which can be divided into unique (non-identical) right triangles, such that all sides of the triangles are integers.
   
2. Find the smallest square which can be divided into non-similar right triangles, such that all sides of the triangles are integers.
   
3. Find the smallest square which can be divided into 8 non-similar right triangles, such that all sides of the triangles are integers.