What are the benefits and disadvantages to alternative investments?

Consider this scenario. Vista Venture Capital is considering an investment in a start-up firm that has developed a new technology for streaming data. If the business is successful, they estimate they will be able to grow to an exit value of $380 million in five years. Vista has agreed to an initial in- vestment of $12 million to fund the early stages of growth and development. If Vista has a 45% required return, what ownership percentage will they demand in exchange for their in- vestment? What three risks are present? How might one mitigate these risks?