Does anyone know how the equation is supposed to look for the radioactive decay lab?

So far, I've gotten to ln(C/150)=-0.024T. I don't know if there is anything else to simplify here, and if there isn't, which number is the half life, or at least, how am I supposed to know which one?

Thanks...

So far, I've gotten to ln(C/150)=-0.024T. I don't know if there is anything else to simplify here, and if there isn't, which number is the half life, or at least, how am I supposed to know which one?

Thanks...