Xiaogang is going to buy a square tablecloth for the round dining table at home. The diameter of the round tabletop is 1.5 meters and the height of the table is 1.2 meters. How many meters should the diagonal be?
小刚准备给家里的圆形餐桌买一块正方形的桌布，量得圆形桌面的直径是1.5米，餐桌高是1.2米，若使铺在桌面上的正方形桌布的四角恰好接触地面，正方形桌布的对角线应是多少米？
<gadget id="calculator">1.2 * 2</gadget>
<output>2.4</output>

<gadget id="calculator">2.4 + 1.5</gadget>
<output>3.9</output>

<result>3.9</result>