16. Strontium-90 undergoes beta decay and has a half-life of 28 years. a) Write the nuclear equation for the beta decay of strontium-90. (2) b) Determine the amount of strontium-90 that would remain 112 years from now if you began with 80 g today. (3) c) What will the daughter-to-parent mass ratio be after 112 years? (1)