A1. The three gifts shown in the picture have the shape of a cuboid with edge lengths of $10 \mathrm{~cm}$, $20 \mathrm{~cm}$, and $30 \mathrm{~cm}$. The lengths of the ribbons, $\mathrm{s}$, with which the gifts are wrapped, are $x \mathrm{~cm}$, $y \mathrm{~cm}$, and $z \mathrm{~cm}$ from left to right, with the loop being the same on all three gifts. Which of the following statements is correct?
![](https://cdn.mathpix.com/cropped/2024_06_07_716acb2f660115fb0b44g-02.jpg?height=354&width=926&top_left_y=951&top_left_x=992)
(A) $x=y=z$
(B) $x>y>z$
(C) $x=y>z$
(D) $xy=z$
A1. On each gift, the ribbon is composed of 8 segments and a loop. 4 segments run along the side faces, 2 along the top face, and 2 along the bottom face. On the left gift, 4 segments are $30 \mathrm{~cm}$ long, 2 segments are $20 \mathrm{~cm}$, and 2 segments are $10 \mathrm{~cm}$. On the middle gift, 2 segments are $30 \mathrm{~cm}$ long, 4 segments are $20 \mathrm{~cm}$, and 2 segments are $10 \mathrm{~cm}$. On the right gift, 2 segments are $30 \mathrm{~cm}$ long, 2 segments are $20 \mathrm{~cm}$, and 4 segments are $10 \mathrm{~cm}$. Therefore, $x>y>z$.