Hi Tankeel,
It's been a couple of years since I did Public law, but this is what the question means to me:
1) It's asking you to define "royal prerogative" and how it relates to the executive's (government's) power.
- For understanding of the royal prerogative, I'd suggest you do some research on Dicey and Bagehot - you'll find the answers there. It's basically referencing the residuary power of the Crown and how it's now vested in modern government (Queen and her Ministers).
- For understanding the concept of the "executive", I'd suggest that you look briefly at the idea of "separation of powers" between the three overarching legal institutions - executive (government), legislator (Parliament) and judicary (courts). You'll find the the powers of the executive are broad, and that parliamentary scrutiny is perpetually missing.
2) Explore the use of prerogative powers by the executive in the context of the Syrian arms crisis.
- Research the different prerogative powers the government has, and see which relate to armormount, international affairs and/or war.
- As a starting point, you'll find that one of the main prerogative powers is that the government can declare and conduct war.
As long as you do the research, I'm sure your essay will be fine!
Fortune1013.