What are two examples of figurative language used in "Mirror" by Sylvia Plath? How can I tell what they mean?

Keep in mind
the definition of figures of speech, which is language that is not meant to
be literal, but makes a comparison between two things which are not alike.  Figures of
speech include both similes and
metaphors.

The two most obvious figures of speech in
this poem are the opening lines of each stanza:

I am
silver and exact.

Now I am a lake.

In
order to decipher what these metaphors may mean, you can answer a few questions:

1. Who is...