A rumor spreads through a population of 1 comma 1,000 people at a rate proportional to the product of the number who have heard it and the number who have not heard it. Suppose 5 people initiated a rumor and 10 people had heard it after 1 day. ?(A) How many people will have heard the rumor after 4 ?days? ?(B) How long will it take for 800 people to hear the? rumor?