Ziconotide is a polypeptide painkiller that blocks calcium ion channels at synapses. In a clinical trial, ziconotide was injected into a patient's cerebrospinal fluid at a rate of 4 ng kg−1 h−14\text{ ng kg}^{-1}\text{ h}^{-1}4 ng kg−1 h−1 for 7 days7\text{ days}7 days.
Given that 1 ng=1×10−9 g1\text{ ng} = 1 \times 10^{-9}\text{ g}1 ng=1×10−9 g:
Calculate the total mass in grams of ziconotide injected after 7 days7\text{ days}7 days into a patient with a body mass of 85 kg.
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