2. Four metal mugs with lids each contain the same volume of hot water at the same temperature. The mugs are made from the same metal and are the same shape and size, but each has its outside surface painted with a different combination of texture and colour.
Which mug radiates thermal energy at the fastest rate?
A the mug painted shiny white
B the mug painted dull white
C the mug painted shiny black
D the mug painted dull black