Polygon abcde rotates 45° clockwise about point f to produce polygon fghij as shown.

what is mbcd?

I think you forgot to give the options along with the question. I am answering the question based on my research and knowledge. It has to be understood first that if the polygon FGHIJ is produced by rotating ABCDE, then "F" is the image of "A" and "G" is the image of "B". So, mBCD is 127 degrees. I hope the answer has helped you.

Explain how you would name a sorting rule for 1 square 1 rectangle and 1 triangle