At 0°C, the speed of sound in the air is 331.5 meters per second, but every time the temperature rises by 1°C, the speed will increase by 0.6 meters. What is the speed of sound when the air temperature is 20°C?
0℃时，声音在空气中的传播速度是每秒331.5米，但是气温每上升1℃，速度就会加快0.6米．当气温为20℃时，声音的传播速度是多少？
<gadget id="calculator">0.6 * 20</gadget>
<output>12</output>

<gadget id="calculator">331.5 + 12</gadget>
<output>343.5</output>

<result>343.5</result>