b. the forces of attraction among them limit their motion.
Answer:
The value is 
Explanation:
From the question we are told that
The operating temperature is 
The emissivity is 
The power rating is 
Generally the area is mathematically represented as

Where
is the Stefan Boltzmann constant with value

So


Answer:
steel
Explanation:
steel because steel has more power to hold something up, where bricks arent as stable