The isotopes `"^57Co` decays by electrons capture to `"^57Fe` with a half - life pf 272d. The `"^57Fe` nucleus is produced in an excited state, and it almost instantaneously emits gamma rays: Find the mean lifetime and decay constant for ` ''_Co^58`

The isotopes ^57Co decays by electrons capture to "^57Fe with a half - life pf 272d. The "^57Fe nucleus is produced in an excited state, and it almost instantaneously emits gamma rays. What will be the activity after one year?

The isotopes "_Co^57 decays by electrons capture to "^57Fe with a half - life 272d. The "^57Fe nucleus is produced in an excited state, and it almost instantaneously emits gamma rays. If the activity of a radiation source "^57Co is 2.0 muCi now, how many "_Co^57 nuclei does the sorce contains?