In order for conduction to transfer heat from one object to another, what must be true? aThe objects should be far apart.

b There must be air circulation.

c The objects need to be touching.

d Solar energy is required.

Awhite powder is added to a solution. the images show observations made before the powder is added, just after the powder has been added, and a little while later. (the liquid in the small beaker is phenol red solution.) what evidence shows that a chemical change has taken place?