$6-34.$ How effectively do you think Katie Beauchamp and Hayley Barna used their time in college to advance their business idea?$6-35.$ In what ways is Birchboxs business approach a win$-$win for both its suppliers and its customers?$6-36.$ How was writing a business plan and preparing for a business plan competition helpful to Katie Beauchamp and Hayley Barna while Birchbox was still in the planning, testing, and prototyping stage?$6-37.$ Going forward, what are the most serious challenges facing Birchbox? Which of these challenges do you believe is the most threatening to the firms success? Do you think Birchbox will have to pivot its business plan again? If so$,$ what factors do you think will precipitate the next pivot?