The half-life of technetium-99 is 213,000 years. After 113,666 years, a sample of technetium-99 has been reduced to a mass of 82.897 mg. What was the initial mass (in mg) of the sample? Round the solution to the nearest whole number.
a) 176 mg
b) 190 mg
c) 205 mg
d) 220 mg