A Bookstore Recorded the Type of Books 30 Customers Purchased $( \mathrm { R } =$

A bookstore recorded the type of books 30 customers purchased during a weekenc sale $( \mathrm { R } =$ romance novel, $\mathrm { S } =$ science fiction, $\mathrm { N } =$ nonfiction, $\mathrm { C } =$ children's fiction). Construct a frequency distribution for the data.
$\begin{array} { l c c c c c } \mathrm { N } & \mathrm { R } & \mathrm { R } & \mathrm { C } & \mathrm { R } & \mathrm { S } \\ \mathrm { R } & \mathrm { C } & \mathrm { C } & \mathrm { S } & \mathrm { R } & \mathrm { R } \\ \mathrm { C } & \mathrm { N } & \mathrm { N } & \mathrm { R } & \mathrm { C } & \mathrm { S } \\ \mathrm { S } & \mathrm { S } & \mathrm { R } & \mathrm { R } & \mathrm { N } & \mathrm { C } \\ \mathrm { S } & \mathrm { R } & \mathrm { R } & \mathrm { C } & \mathrm { C } & \mathrm { N } \end{array}$