Xiaojun said: "There is an angle, which can be measured twice with an angle on the settable, and this angle is an acute angle." How big is this angle?
小军说："有一个角，可以用三角板上的一个角量2次，而且这个角是一个锐角．"这个角多大？
<gadget id="calculator">30 * 2</gadget>
<output>60</output>

<result>60</result>