Hospital New Hire...Now I gotta take an Exam?!

I was offered a "PCA" aka CNA position at a great hospital working in the Mother/Baby Dept. I was informed that I need to come in to take an exam. This is my first experience working at a hospital. Can anyone tell me what I can expect from personal experience? All i know is the test is in writing im assuming multiple choice. I am reviewing my CNA training books. Any advice is welcome thanks