An unknown radioactive element decays into non-radioactive substances. in 30 days the radioactivity of a sample decreases by 12%. when will a sample of 50 mg decay to 10 mg? round your final answer to 1 decimal place.

Time to decay will be 377.7 days.

Step-by-step explanation:

Decay of an radioactive element is represented by the formula

where = Amount after t days

= Initial amount

t = duration for the decay

k = decay constant

Now we plug in the values in the formula

Now we take natural log on both the sides

ln(0.88) =

ln(0.88) = -30k(lne)

-30k = -0.1278

k =

k =

Now we have to calculate the duration for the decay of 50 mg sample to 10 mg.

We plug in the values in the formula

10 = 50

We take (ln) on both the sides

t =

t = 0.37771×10³

t = 377.7 days

Therefore, time for decay will be 377.7 days.

the f

last graph i believe

step-by-step explanation:

worked it out i believe