An ecologist is studying the painted turtle population in a small pond. at the beginning of the year, there are 100 individuals. over the course of a year, 40 turtles are born and 60 die. there is no migration. what is the growth rate (r) of the painted turtle population?

To answer this question, first calculate the birth rate. Out of 100 individuals, 40 were born. Therefore, the birth rate is: 
40/100 = 0.4

Then calculate the death rate. Out of 100 individuals, 60 died. Therefore the death rate is:
60/100 = 0.6

Finally, subtract the death rate from the birth rate to obtain the growth rate:

0.4 - 0.6 = -0.2

Therefore, in this case, the growth rate is negative and the population is in decline.