The Project in Section 6.1 of the textbook asks you to analyze the model of measles pathogenesis that was introduced in Section 5.1, for different levels of immunity c. The animation below allows you to plot the pathogenesis curve for different choices of immunity, and to see which of these results in an individual displaying symptoms. In this animation the total amount of infection is displayed next to the pathogenesis curve, and the area under the curve turns red when this quantity exceeds the threshold requirement for symptoms of 7848 (cells/mL) days.