Answer:
For A it's 13 degrees C. For B it is 15 degrees.
Step-by-step explanation:
Adding positive numbers to a negative number can be put like this:
ex--- -5+9. You have -5 and +9. What you do is flip it around. +9-5 is 4. So. -2+15=+15-2=13.
For B:
from 6 to 0 is 6, and from 0 to 9 is 9. 6+9=15. There's your answers.
Hope it helped!