the half life of strontium 90 is approximately 28 years. find the amount of strontium-90 left from a 10 gram sample after 56 years
.5 = 1 e^-k 28
k =.0247553
? = 10 e^-.0247553 (56)
? = 2.5 gm
After 28 years there will 1/2 of 10gm left = 5 gm
after ANOTHER 28 YEARS there will be 1/2 of 5 gm left = 2.5 gm