The upper and lower bases of a half cylinder are semicircular. It is known that the height of the cylinder and the diameter of the base are both 2 decimeters. What is its side area in square decimeters?
半个圆柱体，上、下底面是半圆，已知圆柱的高和底面直径都是2分米，它的侧面积是多少平方分米？
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 2 * 1</gadget>
<output>6.28</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">6.28 + 4</gadget>
<output>10.28</output>

<result>10.28</result>