Why is efficiency of each ball different? ex (tennis ball) (golf ball) (ping pong ball)

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The us government wants to allocate billions of dollars in the next 10 years to assure our future energy security. the funds will be spread among a variety of possible energy resources. where do you think the government should put the greatest support: solar energy, wind energy, clean coal, oil exploration, gas exploration, or a combination of sources? are there other efforts that should be explored? support your position with cited information for both questions.

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What is the weight of a feather (mass = 0.0001 kg) that floats through earth's and the moon's atmospheres?