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2 years ago

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Question 1

1 answer:

galina1969 [7]2 years ago

7 0

1/f= 1/di+1/do
1/f=1/90m+1/40m
1/f ≈27.7m

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2 years ago

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3 years ago

Read 2 more answers

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3 years ago

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Answer with Explanation:

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