2 goes with the second one (control rods).
3 goes with forth one (mass of unstable fuel)
4 goes with one (shield)
1 goes with third one (moderator)
5 goes with coolant
Answer:
Capitalize places in your sentence. For example, European. I don't understand the rest of your question though.
Can you please use BRAINLY the way it should be used
To Introduce the topic with some indication of its inherent interest or importance, and a clear definition of the boundaries of the subject area.