Use the References to access important values if needed lor this question Radioactive decay can be described by the following equation In A = In Ao - kt where A, is the original amount of the substance. A is the amount of the substance remaining after time t, and ke is a constant that is characteristic of the substance. For the radioactive isotope iron-55, k is 2.67 x 10-2 years If the original amount of iron-55 in a sample is 32,5 mg, how much time is needed for the amount of iron-55 that remains to fall to 13.8 mg? years Submit Answer Retry Entire Group 9 more group attempts remaining