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Deletions are marked like this. Additions are marked like this.
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Part 1b (4 points) : S = E x H and du = dD . E + dB . H at fixed space. Part 1b (4 points) : du = dD . E + dB . H at fixed space and S = E x H. 

Part 1a (3 points) : curl E = - partial_t B,  div B = 0

   100 %: practically perfect
    50 %: only one of the two required answers is given or correct
     0 %: answer missing, or completely incorrect

Part 1b (4 points) : du = dD . E + dB . H at fixed space and S = E x H. 

   100 %: practically perfect
    70 %: correct, except that it was proved only in terms of E and B (no
          consideration of medium)
    25 %: correct starting formula, but no or little development from it
     0 %: answer missing, or completely incorrect

Part 1c (3 points) : Forces: E and H,   Displacements: dv dD and dv dB
                     respectively (dv = d^3 \vec r).

   100 %: practically perfect
    80 %: everything is good, except that dv is attributed to force, not
          displacement
    80 %: left out the dv (d^3 \vec r) part
    70 %: said that D and B are displacments (not dv dD and dv dB)
    60 %: said that B is force, and left out the dv (d^3 \vec r) part for
          the displacements
    50 %: said that B is force, and displacements are D and H (not dv dD
          and dv dH)
    33 %: incorrectly identified dv as the displacments
     0 %: answer missing, or completely incorrect