A radioactive substance decays at a rate proportional to the amount of substance present. If half of the substance decays in 100 years, then what is the decay constant (proportionality constant) ?
1
\(\frac{\ln 2}{100}\)
2
\(\frac{\ln 5}{100}\)
3
\(\frac{\ln 10}{100}\)
4
\(\frac{2 \ln 2}{100}\)