The strain of flu is more virulent, with k=.015. Let's say 10,000 people have been infected by Day Zero out of the vulnerable population of 250,000,000.
B) find out when half population (y = 0.5) has been infected.
C) find when 80% of vulnerable population has gotten that strain
D) Suppose you start with the initial population of 100,000 infectees. Find what value of k will result in 50% of population being infected as of Day 270. If you compute it precisely using logistic function.