What can an underage female do about sexual, physical, and verbal harassment by adults?

I am a 17 year old girl who has just recently gotten a job as a waitress. In the 6 weeks that I have been working, I have been physically, sexually, and verbally harassed. In the first days that I worked there a waiter popped me on my leg with a wet towel and still to this day I have a bruise. That same waiter has played around several times and injured me. Also, the cooks that work at the restaurant, all of which are at least 6 years older then me, have continually gotten worse and worse with sexual harassment. They have slapped my butt, cornered me in one of our walk in freezers and proceeded to touch me inappropriately, and even several times asked to engage in sexual activity. When the owner was informed he just laughed. I have also been threatened by another girl several times to stay away from the cook that she likes, one of those times with a knife in her hands. I was also informed tonight that I have been accused of engaging in sexual activity with the girl’s cook, which she was furious about and her along with another girl proceeded to verbally assault me for the rest of the night until I eventually cried, which they then laughed at and were pleased with. All the while the owner did nothing. I would really like to know if there was anything I could do about this. Thanks