4 gram of a radioactive material of half life 10 years is kept for 15 years. How much of the material will disintegrate?

15/16 part of radioactive material decays in 10 days. After how many days 3/4 part of the material will decay? Find also the half life of the radioactive material.

Define half life. 50% of a radioactive sample decays in 20 years. Find the half life and after how many years 75% of the material will decay.

The average life of a radioactive sample is 2 years. Its half-life in years is

Half life of a radioactive material is 3600 years. Calculate the average life

Half life of a radioactive material is 3600 years. Calculate the decay constant.