Can you plz help with this?

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?

What is the difference between regular convex and concave polygons

Which of the following is the true for f(x) = 5cos