For part (a), find the sum of the first n terms of the geometric series. For part (b), find n for the given sum Sn 7+(-21)+63+(-189)+... a. n=18 b. Sn= 3829​

12. the amount of money in a bank account decreased by 21.5% over the last year. if the amount of money at the beginning of the year is represented by ‘n', write 3 equivalent expressions to represent the amount of money in the bank account after the decrease?

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

There are 18 female students and 16 male students in a class. which of the following expresses the ratio of female students to male students in simplest form? а) 10 b) 9 to 8 c) 8: 9 d)18/16