A paper fan consisting of 9 bamboo sticks evenly formed forms an angle of 144° when fully opened, what is the angle formed by every two adjacent bamboo sticks?
一把由9根竹签均匀组成的纸扇完全打开后成144°的角，每相邻两根竹签所形成的角的度数是多少．
<gadget id="calculator">9 - 1</gadget>
<output>8</output>

<gadget id="calculator">144 / 8</gadget>
<output>18</output>

<result>18</result>