The perimeter of a right-angled trapezoid is 5.8 decimeters, and its two waists are 1.6 decimeters and 1.2 decimeters respectively. How many square decimeters is the product of this right-angled trapezoid?
一个直角梯形的周长是5.8分米，它的两条腰分别长1.6分米和1.2分米，这个直角梯形的而积是多少平方分米？
<gadget id="calculator">5.8 - 1.6 - 1.2</gadget>
<output>3</output>

<gadget id="calculator">1.2 / 2</gadget>
<output>0.6</output>

<gadget id="calculator">3 * 0.6</gadget>
<output>1.8</output>

<result>1.8</result>