Accelertation of the spike?

How would I do this problem?

Because of air resistance a feather's initial velocity was 9.8 m/s. Its final velocity was 5.4 m/s. It took 2 second for the feather to fall. What was the acceleration of the spike?

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Why does it matter? Are we ever gonna use this in life?

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Is this a tryout?

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Answers:    You should probably ask this in the homework section.

What happened to the bird?

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