I need help solving a matrix.
Let B be a 4x4 matrix to which we apply the following operations:
1.double column 1,
2. halve row 3,
3.add row 3 to row 1,
4.interchange columns 1 and 4,
5.subtract row 2 from each of the other rows,
6.replace column 4 by column 3,
7.delete column 1 (column dimension is reduced by 1).
(a) Write the result as a product of eight matrices.
(b) Write it again as a product of ABC (same B) of three matrices.

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