there has been a terrible accident and several people have been injured. you are working in the hospital, taking care of the blood supply. you are low on blood, so you need some volunteers to give their blood. you check on your list of people who have given blood in the past. you find the following information: jennifer has type a blood, rh- amy has type b blood, rh+ emely has type ab blood, rh+ sammy has type o blood, rh - the injured people are rushed into the emergency room. the doctors quickly test their blood to find out what type they will need. they rush the results to you: valentina has type o, rh+ isabella has type ab, rh - who can give blood to valentina?