HELP ASAP

Suppose two people in a larger city with a population of 900,000 get infected with a rapidly spreading virus. Each day the infected person infects 2 additional people. Several students discussing the scenario state the following. Comment on each of the following statements. With which, if any, of these students do you agree? Explain in detail with supporting calculations. If someone is partially correct, explain why.

Argument #1 - Kevin

"Since the number of people in this city is double, the amount of time to infect the entire city will also double."

Argument #2 - Billy

"Since the virus is infecting the people of this city exponentially, the time will be longer, because there are more people, but not doubled"

Argument #3 - Sally

"I did the calculation and even though the population of this city is double, everyone still gets infected the same day!"