A fatal infectious disease is introduced into a growing population.Let S denote the number of susceptible people at time t and let I denote the number of infected people at time t.Suppose that, in the absence of the disease, the susceptible population grows at a rate proportional to itself, with constant of proportionality 0.3.People in the infected group die at a rate proportional to the infected population with constant of proportionality -0.2.The rate at which people get infected is proportional to the product of the number of susceptibles and the number of infecteds, with constant of proportionality 0.001.For the initial conditions S = 100 and I = 500, what happens as t starts to increase?
A)S increases and I increases
B)S increases and I decreases
C)S decreases and I increases
D)S decreases and I decreases

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The Answer of A fatal infectious disease is introduced into a growing population.Let S denote the number of susceptible people at time t and let I denote the number of infected people at time t.Suppose that, in the absence of the disease, the susceptible population grows at a rate proportional to itself, with constant of proportionality 0.3.People in the infected group die at a rate proportional to the infected population with constant of proportionality -0.2.The rate at which people get infected is proportional to the product of the number of susceptibles and the number of infecteds, with constant of proportionality 0.001.For the initial conditions S = 100 and I = 500, what happens as t starts to increase?
A)S increases and I increases
B)S increases and I decreases
C)S decreases and I increases
D)S decreases and I decreases

A Fatal Infectious Disease Is Introduced into a Growing Population