The base of the pyramid is a square, and the four sides are all isosceles triangles. The base angle of each isosceles triangle is about 64 degrees. How many degrees is the apex angle of each isosceles triangle?
金字塔的基底是一个正方形，四个侧面的形状都是等腰三角形，每个等腰三角形的底角大约是64度，每个等腰三角形的顶角约是多少°度．
<gadget id="calculator">64 * 2</gadget>
<output>128</output>

<gadget id="calculator">180 - 128</gadget>
<output>52</output>

<result>52</result>