Answer:
a socket can be driven by a flexible head socket wrench, I believe
Answer:
6.5 × 10¹⁵/ cm³
Explanation:
Thinking process:
The relation 
With the expression Ef - Ei = 0.36 × 1.6 × 10⁻¹⁹
and ni = 1.5 × 10¹⁰
Temperature, T = 300 K
K = 1.38 × 10⁻²³
This generates N₀ = 1.654 × 10¹⁶ per cube
Now, there are 10¹⁶ per cubic centimeter
Hence, 
Answer:
Time =t2=58.4 h
Explanation:
Since temperature is the same hence using condition
x^2/Dt=constant
where t is the time as temperature so D also remains constant
hence
x^2/t=constant
2.3^2/11=5.3^2/t2
time=t^2=58.4 h