Let’s say you are drinking a hot cup of tea. The cup is full and acts as an insulator for the tea. In addition, you are using a spoon to stir your sugar. While in the glass, the spoon is acting as what?

radiator

Explanation:

Provided that the spoon is metal, it acts as a "radiator" which allows the hot temperature of the tea to dissipate or be emitted into the atmosphere. Stirring also allows the central heat in the cup to be transferred to the the cup's edges, thereby allowing it to cool faster.

So, this explains the answer.  

c) up

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