The population (P) of a species of bird in a region is declining rapidly.
The calculation P(t) = 2400 - 180t gives the population in t years from now
a What is the population of birds now?
b
Find P(5) and explain what this means.
c Find t when P(t) = 960 and explain what this represents.
d
Is the function valid for all t> 0? Give a reason for your answer.