In the followin multiplication problem the letters a, b,c, and d represent 4 different digits (cont in details)? what digit would replace each letter?

True is the

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Dynamic symmetry should be the answer

Musical notation is a system which is used to  visually represent music  pertaining to the ear  contend  with instruments or sung by the human voice through  the employment  of written, printed, or different symbols.in the western music tradition, the sound is represented in written form through musical notation.in musical notation, the pitch is indicated exclusively by the position of notes on the lines and spaces of the staff.