Botulinum toxin type A is a therapeutic protein that cleaves SNARE proteins at cholinergic synapses, preventing the exocytosis of acetylcholine into the synaptic cleft.
In a clinical procedure to treat severe focal dystonia, a patient with a body mass of 64 kg receives a localized micro-infusion of botulinum toxin type A at a rate of 1.5 pg kg−1 min−11.5\text{ pg kg}^{-1}\text{ min}^{-1}1.5 pg kg−1 min−1 for a duration of 12.5 hours12.5\text{ hours}12.5 hours.
Given that 1 pg=1×10−12 g1\text{ pg} = 1 \times 10^{-12}\text{ g}1 pg=1×10−12 g:
Calculate the total mass in grams of botulinum toxin type A administered to the patient. Give your answer in standard form.
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