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What does `String.prototype.slice(-3)` do on ‘Hello’?

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What is the difference between `null` and `undefined` in JavaScript?

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What does `Array.prototype.fill(0, 1, 3)` do on `[1,2,3,4,5]`?

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What is the purpose of `delete` operator on object properties?

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What does `encodeURIComponent()` do?

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What is the output of `[1,2,3].reverse()`?

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What does the ternary operator `condition ? a : b` evaluate to when condition is false?

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

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What does `Math.round(4.5)` return?

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Which method checks if a string contains a specified substring?

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What is the output of `’abc’.charAt(10)`?

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What does `!!value` do in JavaScript?

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What is the purpose of `Array.prototype.sort()` default behavior?

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What does `Object.values({a:1, b:2, c:3})` return?

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What is the purpose of `Array.prototype.indexOf()` vs `Array.prototype.findIndex()`?

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What does `String.prototype.split(”).reverse().join(”)` do?

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Which method converts a JavaScript object to a JSON string?

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What is the output of `typeof []`?

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