A semicircular piece of paper has a radius of 1 decimeter. To cut such a semicircle, at least one rectangular piece of paper with an area of how many square meters is needed.
一张半圆纸片半径长1分米，要剪成这样的半圆至少需要一张面积为多少平方米的长方形纸片．
<gadget id="calculator">1 / 100</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">1 * 2 * (1/100)</gadget>
<output>1/50 = around 0.02</output>

<result>1/50 = around 0.02</result>