## Algebra: A Combined Approach (4th Edition)

$a.$ and $c.$ are correct.
To write a decimal as a percent, drop the percent symbol move the decimal point two places to the right and attach the percent symbol, %. $a.$ is correct because $0.231=23.1$% $b.$ is incorrect because $5.12=512$% $c.$ is correct because $3.2=320$% $d.$ is incorrect because $0.0175=1.75$%