Question

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.

Answer 1

so half life is very similar to the last question i just helped you with but instead of using 0.41No you use 0.5No. rearranging the same way gives you t=(ln0.5)/(-k)=5.5 to the nearest 10th

Answer 2

so it will be 5 or 6?

Answer 3

to the nearest tenth its 5.5

Answer 4

last one please