Situation:
 A 30 gram sample of a substance thats used for to sterilize surgircal instruments has a k-value of 0.1253.
 N=Noe^-kt
 No=initial mass( at time t=0)
 N=mass at time t
 k=a positive constant that depends on the substance itself and on the units used to measure time
 t=time, in days
 Find the substance's half-life,in days.Round your answer to the nearest tenth. ...?