One way to control the spread of a disease is to run public health programs that educate people on how to limit their exposure to the disease. For example, frequent handwashing can prevent people from picking up a virus after touching surfaces that may live on. Complete parts (a) and (b). kb cI- dt NSI (a) The epidemic model used is dl dt kb where S(t) represents the number of susceptible people at time t, I(t) represents the number of infected people at NSI-cl that time, coefficient k is a constant of proportionality, coefficient c is the recovery rate, and coefficient b is the number of other people an individual contacts in one unit of time. Explain why in our model such efforts to control the disease would affect the value of the parameter k, but would not affect b or c. Choose the correct answer below. A. Efforts to control the disease will cause more people to survive, increasing N. This will cause the proportion of infected individuals contacted in unit time, k, to decrease but leave variables b and c unaffected. B. Efforts to control the disease will cause the number of infected individuals to decrease. If the total population does not change, then the proportion of infected individuals contacted in unit time, k, must also decrease. The variables b and c should not be affected. OC. Efforts to control the disease will cause the number of infected individuals to increase. If the total population does not change, then the proportion of infected individuals contacted in unit time, k, must decrease to compensate for the increase in I. The variables b and c should not be affected. OD. Efforts to control the disease will cause fewer people to come in contact with one another. This will cause the proportion of infected individuals contacted in unit time, k, to decrease but leave variables b and c unaffected. (b) Suppose that for a particular disease c = 0.6/day, and b = 20/day. What value must k remain below to prevent the disease from becoming endemic? k<