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What does `Object.keys()` return?

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What is the purpose of `try…catch` in JavaScript?

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What does `String.prototype.trim()` do?

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Which method returns the index of the first occurrence of a value in an array?

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What is the output of `typeof undefined`?

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What does the spread operator `…` do when used with an array?

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What does `Array.prototype.filter()` return?

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What is a closure in JavaScript?

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What does the `length` property return for the string ‘Hello’?

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Which method converts a JSON string to a JavaScript object?

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What is the output of `Boolean(”)`?

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What does `Array.isArray([1, 2, 3])` return?

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Which statement correctly creates an object in JavaScript?

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What does the `this` keyword refer to in a regular function called in the global scope (non-strict mode)?

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What is NaN in JavaScript?

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What is the purpose of `Array.prototype.map()`?

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Which method removes and returns the last element of an array?

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What does `console.log(0.1 + 0.2 === 0.3)` output?

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