any of several rules designating allowed transitions between quantum states in terms of the quantum numbers associated with the states.
Basic Spelling Rules ExplainedYou can teach yourself to be a better speller. It is important to realize that learning to spell is a process that is never complete. Spelling is something that everyone has to pay attention to and keep working at it. BASIC SPELLING RULES Short-Vowel Rule: When one-syllable words have a vowel in the middle, the vowel usually has a short sound. Examples: cat, dog, man, …
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