Introductory Topology True/False check - Topology without tears - Exercises 1.1

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I have just started to learn Topology, using specifically the book mentioned in the title. I have placed that information in the title with SEO in mind, if this is not acceptable practice in this community, please re/move it as necessary. I have studied the required MATHJAX and LATEX, and have hopefully written it to a satisfactory level. The questions are listed and my attempts or logic accompany them

If $X=\{a,b,c,d,e,f\}$ and $\tau$ is the discrete topology on $X$, which of the following statements are true?

$a) X\in\tau$: True - Required to be considered a topology.

$b) \{X\}\in\tau$: False - We have the set $a)$, but this is a set within a set.

$c) \{\emptyset\}\in\tau$: False - As above, but in regards to $\emptyset$

$d) \emptyset\in\tau$: True

$e) \emptyset \in X$: True of all sets

$f) \{\emptyset\}\in X$: False as of $c)$

$g) \{a\}\in\tau$: True since $\{a\}\subseteq X$ and the discrete topology takes all possible subsets.

$h) a \in \tau$: False $a$ would need to be a subset. See $n)$.

$i) \emptyset \subseteq X$: True, it is a subset

$j) \{a\}\in X$: False, true of $g)$, but here $a$ would need to be an element to be within $X$

$k) \{\emptyset \} \subseteq X$: False this is a set in a set.

$l) a \in X$: True

$m) X \subseteq \tau$: True

$n) \{a\}\subseteq \tau$: True, since this is a set within $\tau$

$o) \{X\}\subseteq \tau$: False, this is a set in a set.

$p) a \subseteq \tau$: False, this is an element and not a set.

Sorry for the large text wall. Please leave me a comment in regards to things I should avoid doing in my question, and/or any preferable formatting action I can complete. Thank you for your time.