The half-life of a radioactive isotope is 1 h. (a) what fraction of a sample would e left after 3 h: (1) one third, (2) one eight, or 93) on ninth?

The half-life of a radioactive isotope is 1 h. (a) what fraction of a sample would e left after 3 h: (1) one third, (2) one eight, or 93) on ninth? Why? (b) what fraction of a sample would be left after 1 day?