Cabinet reshuffle arrivals and departures

The video introduces Mr. Mercer as the new party chairman and poses a question about the identity of the mods.

Who is Mr. Mercer in the context of the text?

What role does Mr. Mercer hold?

How does the text suggest the role of a party chairman?

What question is posed regarding the mods?

What can you infer about the relationship between Mr. Mercer and the mods?