standard_description: Explain how the unit circle in the coordinate plane enables the extension of trigonometric functions to all real numbers, interpreted as radian measures of angles traversed counterclockwise around the unit circle.
problem_activity: At a local bank, when you open an account, you provide certain information that is stored in the bank's records. The table below shows the names and mailing zip codes of some of the bank's customers.
| **           Customer Name          ** | **           Zip Code          ** |
|----------------------------------------|-----------------------------------|
|             Tyler Jackson              |               70114               |
|            Justine Goodman             |               12084               |
|             Tristan Manuel             |               30311               |
|              Vanera Caro               |               30311               |
|                Mia Lee                 |               20815               |
a.   Suppose
F
is the rule that takes a customer's name and provides their mailing zip code. According to the information in this table, is
F
a function? Explain your reasoning.
b.   Suppose
G
is the rule that takes a customer's mailing zip code and provides their name. According to the information in this table, is
G
a function? Explain your reasoning.
c.   If the bank is looking for a way to identify specific customers, why would using their zip code
not
be a good way to do this? What other input might the bank use instead?


aligns: no