diff --git a/sicp-ex-1.11.rkt b/sicp-ex-1.11.rkt
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diff --git a/sicp-ex-1.12.rkt b/sicp-ex-1.12.rkt
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diff --git a/sicp-ex-1.16.rkt b/sicp-ex-1.16.rkt
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diff --git a/sicp-ex-1.17.rkt b/sicp-ex-1.17.rkt
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diff --git a/sicp-ex-1.18.rkt b/sicp-ex-1.18.rkt
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diff --git a/sicp-ex-1.2.rkt b/sicp-ex-1.2.rkt
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diff --git a/sicp-ex-1.21.rkt b/sicp-ex-1.21.rkt
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diff --git a/sicp-ex-1.23.rkt b/sicp-ex-1.23.rkt
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diff --git a/sicp-ex-1.27.rkt b/sicp-ex-1.27.rkt
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diff --git a/sicp-ex-1.3.rkt b/sicp-ex-1.3.rkt
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diff --git a/sicp-ex-1.7.rkt b/sicp-ex-1.7.rkt
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diff --git a/sicp-ex-1.8.rkt b/sicp-ex-1.8.rkt
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