Question 16 Which pair of symbols is written correctly? KW for kilowatt and MW for megawatt kW for kilowatt and mW for megawatt KW for kilowatt and mW for megawatt kW for kilowatt and MW for megawatt ✓ Bonne réponseExplication The prefix kilo is a lower-case k, while mega is a capital M. A lower-case m is already taken: it is the prefix milli, so mW means milliwatt, not megawatt.
Fondement Définition SI Brochure, 9th edition (BIPM), chapter 3 'Decimal multiples and sub-multiples of SI units': with the exception of da (deca), h (hecto) and k (kilo), all multiple prefix symbols are upper-case letters, and Table 7 gives k for kilo, M for mega and m for milli. Same rule in NIST Special Publication 811, 2008 Edition, section 6.2.2 'Capitalization'.