Bismuth-210 has a half-life of 5.0 days.

  1. A sample originally has a mass of 800 mg. Find a formula for the mass remaining after t days.

    y(t) = `800e^(-ln(2)/5 t)`

  2. Find the mass remaining after days.


  3. When is the mass reduced to 1 mg?


  4. Sketch the graph of the mass function. (Do this on paper. Your teacher may ask you to turn in this work.)