This is a common one at startups (and one of our personal favorites here at The Muse). Hiring managers want to know that you not only have some background on the company, but that you're able to think critically about it and come to the table with new ideas. So, come with new ideas! What new features would you love to see? How could the company increase conversions? How could customer service be improved? You don't need to have the company's four-year strategy figured out, but do share your thoughts, and more importantly, show how your interests and expertise would lend themselves to the job.