Please help me answer all of them correctly. Please help me answer all of them. I would appreciate it, this is my last c

[answerhappygod]

Please help me answer all of them correctly. Please help me
answer all of them. I would appreciate it, this is my last chance,
please. Check it, carefully, please.
1.a.

Please Help Me Answer All Of Them Correctly Please Help Me Answer All Of Them I Would Appreciate It This Is My Last C 1 (58.84 KiB) Viewed 50 times

1.b.

Please Help Me Answer All Of Them Correctly Please Help Me Answer All Of Them I Would Appreciate It This Is My Last C 2 (54.85 KiB) Viewed 50 times

1.c.

Please Help Me Answer All Of Them Correctly Please Help Me Answer All Of Them I Would Appreciate It This Is My Last C 3 (59.24 KiB) Viewed 50 times

The half-life of the radioactive isotope bismuth-214 is 19.7 minutes. How long will it take for the mass of a sample of bismuth-214 to decay from 88.5 micrograms to 15.7 micrograms? minutes

Iron-59 is a radioisotope that is used to evaluate bone marrow function. The half-life of iron-59 is 44.5 days. How many milligrams of a 66.1 milligram sample of iron-59 will be lost by radioactive decay during 133.5 days? mg

Iron-59 is a radioisotope that is used to evaluate bone marrow function. The half-life of iron-59 is 44.5 days. How many milligrams of a 56.8 milligram sample of iron-59 will be lost by radioactive decay during 133.5 days? mg