The half-life of hydrogen-3 is approximately 12.3 years. a. Determine a so that A(t)= Ayd' describes the amount of hydrogen-3 left after t years, where 4, is the amount at time t = 0. Round a to 6 decimal places.

b. How much of a 5-gram sample of hydrogen-3 would remain after 7 years? Round to 3 decimal places.

c. How much of a 5-gram sample of hydrogen-3 would remain after 9 years? Round to 3 decimal places.