Chapter 4 - Review Exercises - Page 316: 23

$1.3450\times10^4$

Numbers in the scientific notation take the form $a\times10^n$ where $1\le a\lt10$ and $n$ is an integer. Hence, in scientific notation, the given expression, $ 13,450 ,$ is equivalent to \begin{array}{l}\require{cancel} 1.3450\times10^4 .\end{array}