Amedical researcher compared the variances in birth weights for five randomly chosen babies of each gender, with the megastat results shown below. the population variances:

Since the action aa batteries last 4 times as long as bonus aa ones, even though they cost four times as much for convenience in only having to change them once compared to 4 times for the same length of time, this is a good reason to buy them. this is especially the case if the batteries are being used in a remote place such as by a geologist with a gps out in the bush then he/she doesn't have to worry about them running down so much.