Question

read the excerpt from \toss of the simmaster\
the numbers that major tallmadge assigned to
members of the culper ring were from a secret writing
system he invented. he substituted digits for words that
would be used in messages. \long island,\ for
example, was 728, \arms\ was 7, and \city\ was 88.
there was a number for each month, such as 341 for
\january\ he made four copies of his codes. he kept
one and gave the others to woodhull, townsend, and
general washington. for words that did not have a
number code, tallmadge gave his agents a cipher. in a
cipher, each letter in a message is replaced by another
letter or a number.
the authors purpose in this excerpt is to
o teach readers about a code system used during the
american revolution.
o persuade readers that ciphers are the greatest
american invention
o argue that major tallmadge made a mistake in
sharing copies of his codes.
o compare the american codes for secret letters to the
british codes.

Explanation:

The text describes Major Tallmadge's code system used during the American Revolution, including number - word substitutions and cipher use. It is informative rather than persuasive (no argument about ciphers being the greatest invention or a mistake in sharing codes) and there is no comparison to British codes.

Answer:

teach readers about a code system used during the American Revolution.