Question 1029823
{{{ f(t) = 30000 / ( 1 + 20*e^(-1.5t)) }}}
(a)
When the epidemic began, {{{ t = 0 }}}, so
{{{ f(t) = 30000 / ( 1 + 20*e^(-1.5*0)) }}}
{{{ f(t) = 30000 / ( 1 + 20*e^0 ) }}}
{{{ f(t) = 30000 / ( 1 + 20*1 ) }}}
{{{ f(t) = 30000 / ( 1 + 20 ) }}}
{{{ f(t) = 30000 / 21 }}}
{{{ f(t) = 1428.57 }}}
1,429 people became ill when
the epidemic began
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(b)
{{{ f(t) = 30000 / ( 1 + 20*e^(-1.5*4) ) }}}
{{{ f(t) = 30000 / ( 1 + 20*e^(-6) ) }}}
{{{ f(t) = 30000 / ( 1 + 20*.002479 ) }}}
{{{ f(t) = 30000 / ( 1 + .04958 ) }}}
{{{ f(t) = 30000 / 1.04958 }}}
{{{ f(t) = 28582.86 }}}
28,583 people were ill by the end 
of the fourth week