Unable to make here phone screen bigger to watch a TWICE concert, Tzuyu decides to craft a rectangular projector screen from a box of the favorite cereal, Oreo OZ, The first step in constructing a box phone projector is to cut a rectangle from a sheet of white paper such that it has the same dimensions as the base of the cereal box. The piece is then placed at the bottom of the box to be used as a projection screen. Tzuyu likes a challenge. So, rather than tracing the box's base on the copy paper as a guide to cut the rectangle, she decides to measure the base. Unfortunately, she broke her ruler the other night trying to hit a fly! Suddenly, a Magic Mochi materializes before Tzuyu. The Magic Mochi says: "Tzuyu: do not despair! I have three secrets about the Oreo Oz cereal box that will help you!" "Secret