Based on the temperature in the various cities, we can calculate that it was 13° C warmer in Shanghai than in Harbin.
Temperature in Shanghai was:
= Temperature in Beijing + Difference in temperatures
= -2 + 7
= 5°C
Temperature difference between Shanghai and Harbin is therefore:
= 5 - (-8)
= 5 + 8
= 13°C
In conclusion, it was 13°C warmer.
Find out more about temperature differences at https://brainly.com/question/26039737.