The half-life of "Co is 5.27 years. The activity of an Co sample is 4.20 x109 Bq. What is the mass of the sample? Express your answer with the appropriate units. View Available Hint(s) HA ? m = 3.13 . 10-6 g Submit Previous Answers X Incorrect; Try Again; One attempt remainingThe radium isotope Ra, an alpha emitter, has a half-life of 11.43 days. You happen to have a 1.0 g cube of Ra, so you decide to How long will it take the water to boil? use it to boil water for tea. You fill a well-insulated container with 500 mL of water at 16" and drop in the cube of radium. Express your answer with the appropriate units. At = 8.4 S Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remainingA 50 kg laboratory worker is exposed to 20 mJ of beta radiation. What is the dose equivalent in mrem? Express your answer in millirems. AEd ? DE= 0.4 mrem Submit Previous Answers Request