Help me plz.

If a is a nonzero real number then the reciprocal of a is

To decrease an amount by 16% what single multiplier would you use

Evaluate the function , when d = {9, 15, 30}. r = {5, 7, 12} r = {6, 10, 15} r = {6, 10, 20} r = {5, 12, 20}