If the apex angle of an isosceles triangle is 110°, what is the base angle of it?
等腰三角形的顶角110°，则它的一个底角是多少°．
<gadget id="calculator">180 - 110</gadget>
<output>70</output>

<gadget id="calculator">70 / 2</gadget>
<output>35</output>

<result>35</result>