The point $P$ with polar coordinates $(r,\theta)$ is such that
$OP=r$ and the angle between the x-axis and the line through $OP$
is $\theta$ measured counter clockwise. Equivalently if $P$ has
Cartesian coordinates $(x,y)$ then $x=r\cos \theta$ and $y=r\sin
The question asks for an explanation of the features of the graph.
If you want to use a software package to sketch the graph you may
want to download the shareware graphing software Graphmatica