Radioactive Decay

Please address/correct the below 5 issues found on the attached assignment:
1) T2- Review this one. There is a factor 1000 times attached to the rate indicated on the y-axis. Then in the next 2 column, it is a time that should be registered.
2) T6 and T7- The data for half-life are incorrect: the log used here is Ln. Ln(2) = 0.693
3) Q2- it should appear in T2 once it is corrected.
4) Q4- After data revision, you may have another answer.
5) Q10-Can decay be exactly predicted?