For each of the following spaces:
determine whether it is compact; and
determine the largest natural number \(i\) for which it satisfies the separation axiom \(T_i\).
Consider:
\(\mathbb R\) with the excluded-point topology;
\(\mathbb R\) with the included-point topology;
the lower-limit line \(\mathbb R_\ell\);
the subspace \([0,1]\subset\mathbb R_\ell\).