1. cat command is specific to unix (linux). It does not work on windows. But certain commands such as pwd ( print working directory )

    works on windows. I have installed Python & IPython on my Windows 7 ( Professional )

2. The last question the answer is not correct. The question is "Given a file data.txt with 3 columns of data separated by spaces, read 

     into 3 separate simple sequences. The answer in the video is :

     x = loadtxt("data.txt", unpack = True, delimiter=":")

    Answer should be =>

    x, y, z = loadtxt("data.txt", unpack=True, delimiter=":")

3. Second Question also the answer is incorrect. We should be using 3 variables on the LHS