The school is going to hold a kite competition, and Xiaohong plans to design a kite herself. The design requires that the shape of the kite is an isosceles triangle, and one of its top angles is 40°. Calculate how many degrees are the two base angles of this kite?
学校要举行一次风筝比赛，小红准备亲自设计一个风筝．设计要求这个风筝的造型是等腰三角形，它的一个顶角是40°．计算一下这个风筝两个底角各是多少度？
<gadget id="calculator">180 - 40</gadget>
<output>140</output>

<gadget id="calculator">140 / 2</gadget>
<output>70</output>

<result>70</result>