Activity of a Nocturnal Animal Many activities of living organisms are periodic. For example, the graph at the right below shows the time that a certain nocturnal animal begins its evening activity. (a) Find the amplitude of this graph. (b) Find the period. (c) Write the equation y=f(x) that represents the graph in the picture, where x=1 represents the month of January, y is the time of the day and y=0 represents 6:00 PM. Time P.M. Activity of a Nocturnal Animal 8:00- 7:30- 7:00 6:30 5:30 Apr Jun Aug Oct Dec Fe Apr 5:00- 4:30- 4:00 Month