a) White to mate in one.

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b) White to mate in one.

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c) White to mate in two.

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d) White to mate in three.

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Solutions:       a) B-d5 mate                     b) B-h6 mate                       c) B-d7, P-a5  followed by   B-b6 mate

                            d) B-e6ch, K-b8   then  B-f4ch, K-a8    followed by  B-d5 mate