Answer :
Well town A has an annual growth that stays constant. town B has a 10% growth which is exponential because it takes a percent of the whole number and adds it so if you have 145 residents in 2006 in say three years in 2009. in 2007 its population would be 159.5> rounded up because you can't have half a person it would be 160. in 2008 it would be 176 and finally in 2009 it would be 194. that's a growth of 49 in three years where as town a grows only ten people per year. which means town a would only grow by 30 people in three years and have a population of 175.