Some ecologists divided a female bird population into three categories: juvenile left parenthesis up to 1 yr o l d right parenthesis comma subadult (1 to 2 yr old), and adult (over 2 yr old). They concluded that the change in the makeup of the bird population in successive years could be described by the matrix equation below. The numbers in the column matrices give the numbers of females in the three age groups after n years and n + 1 years.