a.
∠1 and ∠2 are supplementary angles, therefore:

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b.
∠5 and (∠3 + ∠4) are supplementary, so:

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c. ∠4 can be found using the triangle sum theorem:

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d. ∠6 and (∠7 + ∠8) are supplementary, so:

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e.
∠7 can be found using the triangle sum theorem, so:

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f. ∠9 and ∠10 are supplementary, so:

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g.
∠10 and (∠7 + ∠8) are corresponding angles, so:
