Solution: Divide the tree into 7 sections, each section is a week, take a section of the tree and expand it into a rectangle, with vines as the diagonal of the rectangle. The length of the side rectangle is the circumference of the trunk, not 3 feet, and the width is 20/7. Diagonal length: √ [3 2+(20/7) 2] = (√ 8,465,438+0)/7 The total length of vines is the sum of 7 segments: (√ 8,465,438+0)/7 * 7 = √ 8,465,438+.