'''
Radioactive decay

In this exercise you will simulate the radioactive decay of polonium, with a 
half-life of 388 years. Start with 1,000 radioactive atoms and follow the 
decay for 4,000 years, indexing the current number of atoms every ten years. 

Exercise A. Exponential 
Plot the number of radioactive polonium molecules versus time, using 
that N(t) = N_0 * (1/2)^(t/t_{1/2}), where 
* N(t): The number of radioactive atoms remaining at time t
* N_0: The initial number of radioactive atoms
* t: Time elapsed
* t_{1/2}: The half-life of the substance
'''

# Your code here


'''
Exercise B: Stochastic

Radioactive decay is a stochastical process. Instead of following a nice 
exponential, each atom has a 1/388 chance to decay per year. 

Write a `for` loop, in which `np.random.rand()` is used to simulate how many 
molecules decay within those 10 years. Then, plot the amount of molecules every
ten years as well as the theoretical result in one plot. 

Don't forget to add a legend. 
Add a second, zoomed in plot of a section (use subplots!).

Note: `np.random.rand()` gives a random number between 0 and 1 from a uniform 
distribution. We can use it to simulate stochastic events by writing code that
effectively says "do x only if np.random.rand() < 1/388".
'''

# Your code here