Consider the $($directed$)$ network on the left$-$hand side, below. We could represent this network with the set of Prolog statements on the right$-$hand side, below.

$1$ ink $(a,b).$

$1$ ink $(a,c).$

$1$ ink $(b,c).$

$1$ ink $(b,d).$

link $(c,d).$

link $(d,e).$

link $(d,f).$

link $(e,f).$

link $(f,g).$

Now, given this network, we say that there is a connection from a node $x$ to a node $Y$ if we can get from $x$ to $Y$ via a series of links. For example, in this network, there is a connection from a to d$,$ and a connection from $c$ to $f,$ etc.

s$).$ Formulate the appropriate Prolog rule connection $(x,Y)$ which is true if there is a connection from $x$ to $Y$ as described above $-$ note that this rule will be recursive. Test this rule out on the above network, to see if it is working correctly.

Once it is working correctly, you will note that, e$.$g$.,$ the query connection$($a$,$e$).$ will give true multiple times. This means something, actually. this mean?