If the temperature of a substance increases, you can conclude that the value of q (heat) is positive.

Here's why:

* Heat (q) is the transfer of thermal energy between objects or systems at different temperatures.

* Positive q indicates that heat is flowing into the substance, causing its temperature to rise.

* Negative q indicates that heat is flowing out of the substance, causing its temperature to decrease.

In simpler terms: When you add heat to something, its temperature goes up.