For each of these intervals, list all its elements or explain why it is empty. a) [a, a] c) (a, a] e) (a, b), where a > b b) [a, a) d) (a, a) f) [a, b], where a > b

Frank owns a $141,000 home, for which he has a 30-year mortgage in the amount of $700 a month. once he has paid off mortgage, how much will he have paid in investment? a. $111,000 b. $109,000 c. $120,000 d. $141,000