dy
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4 A certain rumor spreads through a. oommumty at the rate a? =_ 2y (1-.— y), where y is the
proportion of the populahon that has heard the tumor 'at time t. ‘ /
0“ FINA hm
ea)» (y) D
b. Wkai' rm’borhm 0" he Parade-hm ha
5 A He. rum“ -
CPI