02:20:27 Read this excerpt from part 5 of Zeitoun.
Albo
Progress is being made. It's so slow sometimes, so terribly so sometimes, but progress is being made. We
have removed the rot, we are strengthening the foundations. There is much work to do, and we all know what
needs to be done. We can only do the work, he tells Kathy, and his children, and his crew, his friends, anyone
he sees. So let us get up early and stay late, and, brick by brick and block by block, let us get that work done.
Which word best describes the tone of this excerpt?
sentimental
optimistic
supportive
O demanding
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The kidney filters potentially toxic substances in the blood, and thus “clears” the blood of those substances. this clearance function is dependent upon and proportional to the diffusion gradient of the substance across filtering capillaries, i.e. if the concentration of the substance is doubled, twice as much will be cleared from each ml of blood that is filtered. suppose that the body produces a constant amount of a substance x per unit of time. the kidneys eliminate substance x at a rate directly proportional to the concentration of the substance and the volume of blood cleared each minute (c): elimination = c × [x], where [x] is the steady-state concentration of substance x. imagine an individual with an initial concentration of x equal to [x]0 who develops kidney disease. her baseline clearance c0 drops to one half of the original (½c0). what is the new steady state concentration of x? (for simplicity, assume that substance x is 100% filtered by the kidney).