I have a Biology degree with no major sales experience....needless to say I had this one covered but a lot of people just say the wrong things. Mention how much you love the competition and challenges it involves. They are life skills that are important in everyday life. Who wouldnt want to learn these skills? As for why enterprise? Well thats personal. Think seriously why you would want to work there and be honest about it. Theres nothing worst then an answer that is dry and can be used for any job. Make it specific and how you will not only help them but they will be helping you as well.