Answer:
-60°C
Explanation:
According to this question, a material was cooled from 100ºC to 40ºC.
The temperature change, which is symbolized by ∆T = final temperature - initial temperature
That is, ∆T = T2 - T1
In this question, T2 = 40°C, T1 = 100°C
Hence, ∆T = 40°C - 100°C
∆T = -60°C
