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In this paper, A and C will denote 4??4 reducible companion matrices, we combine the Kronecker product, Hadamard product with numerical rang of matrices, discuss the relations between the Kronecker product, Hadamard product with numerical rang of matrices, and illustrate that the Kippenhahn curve CR (C ) consists of CR (A) consists of one ellipse whose foci are ??1 = ??3 = -a2/a??2i, ??2 = ??4 = a...