At the same time, the temperature in Shanghai is 5°C and that in Harbin is -15°C. What is the temperature difference between the two places?
在同一时间里，上海的温度为5℃，而哈尔滨为-15℃，两地温差是多少．
<gadget id="calculator">5 - (-15)</gadget>
<output>20</output>

<result>20</result>