Answer:
I'm not 100% sure but it could be -1
Step-by-step explanation:
Line all of the numbers up to get
-11, -8, 7, 18
Between the second and third highest temperature (-8, 7)
-8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7
I just crossed off each and the one left in the middle was -1
