N(t)=N(0)e^?t

N(t)=N(0)e^{?\lambda t}

N(t)=N(0)e²t²

N(t)=N(0)e²t⁴

the time in which N has been reduced to one-half of a standard fixed amount

the time in which N has been increased to double its initial value

the time in which N has been reduced to one-half of its initial value

None of the above

the average time a radionuclide continues to emit

the time at which N has been reduced to?e^?1of its initial value

the most probable time a radionuclide continues to emit

the time at which N has been reduced to one-half of its initial value

???rays

X rays

Y rays

None of the above

3200 years

2400 years

4800 years

6400 years