Easy solution

one

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1. Rxh7 kg8 2. Qf7 1-0

Two

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1. Qd8+ Kh7 2. Qf8 (any move) 3. Qg7#

Three

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1. Qe8+ Kh7 2. Qe4+ (Kg8 or g3) 3. Qxd5 1-0

Four

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1. Rf7+ Kg8 2. Re7+ Kf8 3. Qf7# 1-0

1. Rf7+ Kg8 2. Re7+ Kh8 3. Qc8# 1-0

1. Rf7+ Kh8 2. Qc8# 1-0

1. Rf7+ Kh6 2. Qh4# 1-0

Five

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1. ... Qf4 # 0-1

six

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1. ... Rgxg3# (Rdxg3)# 0-1

seven

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1. Qe8+ Rxe8 2. Rxe8# 1-0

eight

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1. ... Rc1+ 2. Kf2 Qf1+(Qd2+) 3. Kg3 Nf5+ 4.Kh3 Nxh4 0-1

1. ... Qd1+ (Qb1+) 2. Kf2 Rc2+ 3. Kg3 Nf5+ 4.Kh3 Nxh4 0-1

nine

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1. ... Qxb7 2. Nxb7 Rxd1+ 0-1 (Black has a extra rook)

ten

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1. Qd6+ Ke8 2. Qd7+ Kf8 3. Qxf7# 1-0

Eleven
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1. Rc5+ Kh4 2. Qg3 (Qg5)# 1-0

Twelve
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1. Bh5# 1-0