*☆*――*☆*――*☆*――*☆*――*☆*――*☆*――*☆*――*☆**☆*――*☆*――*☆*――*☆
Answer: Something that's vibrating, and you also need medium for those vibrations to start in.
I hope this helped!
<!> Brainliest is appreciated! <!>
- Zack Slocum
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Answer:

Explanation:
As we know by first law of thermodynamics that for ideal gas system we have
Heat given = change in internal energy + Work done
so here we will have
Heat given to the system = 2.2 kJ
Q = 2200 J
also we know that work done by the system is given as

so we have



Definitely not the last 2. My bet is on the first option. If it is wrong don't hit me please...
True . this is called a complex substance
B)is pills everything to the surface of the earth not sure about A