How to understand the Python Numpy function argmin() and argmax() with bool type

Question

I'm new to python, and now try to understand the argmin() and argmax() function in Numpy.

The code for example is shown as follows:

import numpy as np
b = np.array([4,9,13,20])
print(b.argmin(),b.argmax())

it returns '0' and '3', which represent the locations of the minimum and maximun of the array.

Now we turn to another example:

import numpy as np
b = np.array([4,9,13,20])
c = b>10  #array([False, False,  True,  True])
print(c.argmin(),c.argmax())

The results are 0 and 2. How to understand the 0 and 2 in the results?

In my opinion, the 2 means the first occerrence of the 'True' in c, but how do we understand the 0 in the result?

Anyone can explain? Thanks.