Concept explainers
Spread of News A news item is spread by word of mouth to a potential audience of
people will have heard the news. The graph of this function is shown in Fig. 7.
Figure 7
a. Approximately how many people will have heard the news after
b. At approximately what rate will the news spread after
c. Approximately when will
d. Approximately when will the news spread at the rate of
e. When will the news spread at the greatest rate?
f. Use equations (9) and (10) to determine the differential equation satisfied by
g. At what rate will the news spread when half the potential audience has heard the news?
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