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    I'm really stuck on the following question and I feel like I'm simply not understanding something basic about the topic, but I can't figure out what that might be. Any help would be greatly appreciated.

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    The way I've tried to solve it was by writing:

    V=102h - kh^0.5 +2t

    Then finding that dh/dV = 1/100 - (2h^0.5)/k
    And dV/dt = 2

    I've also tried starting with dV/dt = 2 - kh^0.5

    After that I just plug this into dh/dt = dh/dV * dV/dt

    Either way I get a wrong answer.

    Of course this method works perfectly if you assume that V=100h and therefore dh/dV = 1/100
    But surely that can't be right, as dV/dt clearly suggests that there's more terms involved in the value of V. Not just 100h.

    The correct answer is supposed to be (2-kh^0.5)/100.

    How do I even begin with a problem like this?

    Thank you in advance for your time and assistance.
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