Your friend zahra has been in a relationship with isaac for a couple of months. isaac has just told zahra that he has tested positive for an sti. you know that they do fool around occasionally, and have engaged in oral sex. zahra tells you that she is not worried because they have not had sexual intercourse yet, and she does not have any symptoms. zahra tells you she is thinking about having sex with isaac this weekend since isaac has already seen a doctor. what advice should you give zahra? check all that apply. isaac should be cleared by a doctor before he and zahra engage in further sexual contact. zahra should get tested because she may also be infected. zahra does not need to get tested since she and isaac have not actually had sex yet. zahra and isaac should use a condom to prevent sti transmission even if they are only having oral sex. zahra does not need to see a doctor because she does not have any symptoms of an sti.