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\frac{\mathrm{d} \mathrm{P}}{\mathrm{dt}}=\frac{\mathrm{d} \mathrm{b}}{\mathrm{dt}}+\frac{\mathrm{d} \mathrm{h}}{\mathrm{dt}}+\frac{\mathrm{d} \mathrm{C}}{\mathrm{dt}}=(3)+(-3)+\frac{6}{\sqrt{394}} > 0