_____add or remove one or more classes from each element in the set of matched elements, depending on either the class's presence or the value of the state argument.
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The adjacent sibling combinator (_____ ) separates two selectors and matches the second element only if it immediately follows the first element, and both are children of the same parent
jQuery _____ Method Set Attribute
_____Bind an event handler to the "dblclick" JavaScript event, or trigger that event on an element.
_______method is a handy helper for working with JSON directly if you don’t require much extra configuration