Your employer must pay you for a minimum of three (3) hours work if he called you in, or you showed up for your normal workday and were sent home early.
Yes, the law says the employer must pay you at least minimum wage for any work you do.
As a general rule, your employer must pay you at least every sixteen (16) days.
Your employer must pay you for the time you spend travelling if it is part of your job. This does not include the time you spend going to and from work each day.