The incoming water has pollutant concentration c(t) = 10(1 -I- cost) that varies betwe...

The incoming water has pollutant concentration c(t) = 10(1 -I- cost) that varies between 0 and 20, with an average concentration of 10 and a period of oscillation of slightly over months. Does it seem predictable that the lake's polutant content should ultimately oscillate periodically about an average level of 20 million liters?

Verify that the graph of x(t) does, indeed, resemble the take- the pollutant concentration in the reservoir to reach oscillatory curve shown in Fig. 1.5.9. How long does it 5 ?

Reference of Fig. 1.5.9