Answer:
270
Explanation:
The figure B is just one 90° rotation away from becoming A, i.e.,
If we rotate B 90° counterclockwise, we get A.
To obtain the same figure after rotating it (counterclockwise or clockwise), the minimum degrees required are 360
So, B becomes A after 90° of rotation, while A becomes A after 360° rotation (in the same direction)
That means,
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(angle of rotation is the angle which A turns about in order to line itself with B)
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That makes it 270°