Question

A substance experiences rapid changes in temperature over the course of an experiment to test its electrical conductivity.

At the start of the experiment the substance is measured to be 70°C, and by the end of the experiment its temperature is measured as −60°C.

Answer 1

130

Explanation:

when u you have to subtract you do keep, change, change so it would 70 + 60 instead of 70 - (-60)