# Question #2eecb

##### 1 Answer

#m(t)=100e^(-ln2/1590t)# . Mass in grams and time in years.#m(t=1000)=100e^(-ln2/159xx100)# #t_(30g)=-ln0.3/ln2xx1590 years# #m'(t)=-(10/159ln2)e^(-ln2/1590t)#

#### Explanation:

Nuclear decay is a

Solving the differential equation gives

To find

Using

Answer

Question 2; just plug in the value

Question 3;

Question 4; I assume

This gives the rate of change of your radium in 1000 years time.