As a result of the single intake of 6.3 kBq of a radionuclide, a certain organ of the body will receive a dose during the next 50 years of 0.20 mGy from beta particles and 0.15 mGy from alpha particles. The organ has a tissue weighting factor of 0.05. 

(a) If this radionuclide has a radioactive half-life of 15 hours and the biological half-life of 10 days, calculate the effective decay constant of this radionuclide in the unit of sec -1 . 

(b) Calculate the committed equivalent dose to the organ. 

(c) If this organ is the only tissue irradiated, calculate the committed effective dose. 

(d) What is the annual reference level of intake (ARLI) for this route of intake? The ARLI is defined as “the activity of a radionuclide that, taken into the body during a year, would provide a committed effective dose to a person, represented by Reference Man, equal to 20 mSv. The ARLI is expressed in Bq.”