Answer
See the explanation below
Work Step by Step
Given $f(x) = \log_{a} x$ for a = 2, e, 5, 10
The question asks for all of these graphs on the same screen and the relation between the four.
Since $f(x) = \frac {\log x}{\log a}$
$f(x) = \frac{1}{\log a} * \log x$
It is just a vertical stretch by a factor of $\frac{1}{\log a}$
So if a = 2, then the vertical stretch is by a factor of $\frac{1}{\log 2}$
If a = 5, then stretch = $\frac {1}{\log 5}$, etc.