NUCLEAR PHYSICS RADIOACTIVE HALF LIFE Each of the following questions refers to the graph below that plots the activity of a radioactive sample as a function of time. Activity vs Time 3000- Activity in Bq 2500- 2000 ...... -i . ... 1500 1000 - 20 40 60 80 100 120 1 140 160 180 200 220 240 260 280 300 320 340 360 380 400 Time in Seconds 1. What is the half-life of this radioactive sample? 2. What is the decay constant of this isotope? 3. How many, atoms were initially present in this sample? 4. What will be the activity of this sample after 10.0 minutes? 5. How long will it take for the activity of this sample to drop to 1.0 % of its initial value? 6. How many radioactive atoms will remain after 10.0 minutes? 7. How many radioactive atoms will have decayed during the first 5.0 minutes