Answer:
a)1.404 E-10 m^2/s
b)1.438 E-12 m^2/s
Explanation:
Diffusion Coefficients can be calculated at different temperatures taking into account the energy of the diffusive process, remember that this process takes place in the interstices of the solid, and gets with higher temperatures due to the higher kinetic energy of the particles.

a) For α-iron (BCC)

b) For γ-iron (FCC)

This kind of questions cannot be open because there might be many different answers depending of the focus.
In fact, I found the set of options that comes with this questions. This is:
A. behavior of ions.
B. molecular bonding.
C. molecular shape.
D. molecular motion.
Of course, the answer is the option D. molecular motion.
And, of course, you need an explanation.
It is good to know that the word kinetic refers to motion, so definetly kinetic molecular theory is a theory about the motion of the molecules.
With that you likely had been able to answer the question. But it is good to know what the molecular theory is.
The molecular kinetic molecular theory explains the properties and behavior of the gases in terms of the motion of its particles (molecules) making several assumptions about the energy, size and motion of such particles.
I believe D. because all the organisms that live in a lake can be a bunch of living things that would be considered a population and not a species. I canceled out B. from the get go because, I don’t believe non living organisms can be in a population ?
Please get back to me if I’m right or wrong :)
Answer:As predicted by VSEPR theory, the molecule adopts a "bent" molecular geometry similar to that of water.
Explanation: