Answer:
Starting population of crickets is 50. It doubles in size every 4 months.
5 years = 60 months
60 : 4 = 15
The equation is:
f ( x ) = 50 * 2^x ( an exponential function )
f ( 15 ) = 50 * 2^15 = 50 * 32,768
f ( 15 ) = 1,638,400
Answer: A ) 1,638,400