The rate of increase of the number of working married couples ( in millions ) in the United States from 2 0 0 8 can be modeled by ' ( ) = 0 . 0 9 1 8 2 - 1 . 9 8 8 + 1 0 . 2 8 where is the time in years, with = 8 corresponding to 2 0 0 8 . The number of working couples in 2 0 1 4 was 3 1 . 7 million ( Hint: This is an initial value problem ) a ) Determine a function that can model the total number of working married couples as a function of time b ) How many couples, according to part ( a ) were in 2 0 1 0