I think it is fine the way it is.  It nicely indicates that I want 4 numbers.  If I omitted the "num" argument, I would have to explain it elsewhere, or make them look up the documentation.
0) Looking at the help for np.linspace indicates it is an optional argument (because a default value is already defined).
1) It's a matter of style.  They could use ```np.linspace(num=5, stop=10, start=1)``` if they wanted to.
2) it is a detail about python that is irrelevant to numpy. (positional arguments vs keyword arguments).
3) the python tutorial gives several, very clear ways to specify function arguments
5) those doing the lab are smart people, they will discover it eventually.