Select the situation in which one quantity is changing at a constant rate in relation to the other quantity. a. barry spends $9 on lunch daily. b. the market value of a new computer decreases by 6% every year. c. nathan's investments increase in value by 13.5% each month. d. the number of ants in a colony doubles every 8 weeks.

Choice A is the only one that is changing at a constant rate. The reason is that for all three other choices the new rate is based on a different amount after the percent has been applied or the doubling of the ants has been applied. The price per day for the lunch Is constant because whatever the number of days is the amount would always stay the same for each of those days.