. (c) The
graph of is increasing where
is positive, concave upward
is increasing, and concave downward where
decreasing. Thus the graph of is
always increasing, concave upward between and
concave downward between
Use , , and the condition when
. When , 99.98%.
The rate of increase begins to decrease between 1983 and 1984, so
half capacity is about 1900, making the carrying capacity about 3800.