2. ELECTRICAL ENGINEERING
SCORE: 6.0/10

Strengths:
- Uses the correct 3-phase voltage-drop equation with R·cosφ + X·sinφ.
- Correctly calculates 252 A starting current and handles the 0.30 starting PF.
- Numerical cable-drop calculations are internally consistent with the stated R/X assumptions.
- Correctly separates ampacity from voltage-drop performance.

Major errors:
- Direct contradiction: first says X·sinφ is "dominant," then correctly calculates it as only ~17% of cable impedance drop.
- Treats 5% as a NEMA MG 1 starting-voltage-drop limit; that is not a general motor-start acceptance criterion.
- Actual starting terminal sag cannot be assessed from cable impedance alone; transformer/source impedance is essential.
- NEC motor conductor sizing is not simply 42 A < 65 A. Motor conductor rules generally involve 125% of applicable motor FLC plus installation/termination/derating requirements.
- Assumes THHN/THWN-2 and a 75°C ampacity column despite those conditions not being given.
- The assumed 0.10 mΩ/m reactance is plausible only as an estimate and materially affects the starting result.

Verdict:
Good engineering mathematics, but insufficient code discipline and an overconfident final "pass." The defensible conclusion is that 6 AWG appears plausible for cable voltage drop under stated assumptions, while total starting-voltage performance and NEC compliance remain unproven.