Salesforce JavaScript Developer I Cert Practice Exam ALL ANSWERS 100% CORRECT SPRING FALL-2023/24 EDITION GUARANTEED GRADE A+

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Which two syntax examples correctly initialize a value to the variable strLang? A. let strLang = 'javascript'; B. const strLang = 'java' + 'script'; C. let strLang = javascript; D. str strLang = '... javascript'; ANSWER: A. let strLang = 'javascript'; B. const strLang = 'java' + 'script'; Additional Info: Note that C doesn't have a value that has single quotes around the word 'javascript' and for D, 'str' is not a proper identifier Which statement sorts the following number array so it is in ascending order? const arr = [7, 3, 400, 10]; A. arr.sort(); B. arr.sort((a, b) => a - b); C. arr.sort((a, b) => a < b); D. arr.sort((a, b) => b - a); ANSWER: B. arr.sort((a, b) => a - b); Additional Info: A. The sort() function sorts values as strings, which will sort this as [10, 3, 400, 7]. C. The compare function expects a positive, negative, or 0 to be returned. D. The compare function will actually reverse the order of the numbers. Which statement sorts the following string array so it is in descending order? const arr = ["Banana", "Orange", "Apple", "Mango"]; A. arr.sort(); B. arr.sort((a, b) => a - b); C. arr.reverse(); D. arr.sort((a, b) => b - a);ANSWER: C. arr.reverse(); Additional Info: A. The sort() function sorts values as strings in ASCENDING order: ["Apple", "Banana", "Mango", "Orange"]; B,D. Expect a number array. What are the different data types used in JavaScript? ANSWER: There are 8 basic data types in JavaScript: 1. Number for numbers of any kind: integer or floating-point, integers are limited by ±((2^53)-1). 2. BigInt is for integer numbers of arbitrary length. 3. String for strings. A string may have zero or more characters, there's no separate single-character type. 4. Boolean for true/false. 5. NULL for unknown values - a standalone type that has a single value null. Note, typeof null returns "object" even though it is NOT and object. 6. Undefined for unassigned values - a standalone type that has a single value undefined. 7. Object for more complex data structures. 8. Symbol for unique identifiers. Which collections of data are ordered by a key? ANSWER: Map and set objects. What is the proper syntax for adding placeholders in template literals? ANSWER: Use a dollar sign followed by curly brackets: ${expression}. Additional Info: let name = "John"; // embed a variable alert( `Hello, ${name}!` ); // Hello, John! // embed an expression alert( `the result is ${1 + 2}` ); // the result is 3Note this only works if you use backticks, `, and not single(') or double(") quotes otherwise the results will be shown as literal, ie: Hello, ${name}! How do you instantiate a value as a BigInt? A. Nothing, JavaScript will automatically cast a number to a BigInt if the value is greater than ((2^53) - 1) B. const bigInt = BigInt.parse(1234567890123456789012345678901234567890); C. const bigInt = 1234567890123456789012345678901234567890n; D. const bigInt = BigInt.parse('1234567890123456789012345678901234567890'); ANSWER: C. const bigInt = 1234567890123456789012345678901234567890n; Additional Info: BigInt does NOT work in IE. Given the following Animal constructor: function Animal(size, age) { this.size = size; this.age = age; this.canTalk = false; } Which method creates a new instance of the object? A. Object.create('Animal'); B. new Animal('large', 10); C. Object.prototype(Animal); D. Object.new(Animal); ANSWER: B. new Animal('large', 10); Additional Info: A. The create method needs the object name without quotes. C. This is an incorrect way to use a prototype. Prototypes are used to add methods to existing constructors. D. This is not the correct way to use the new keyword. It is not a method. A developer wants to use a module called DatePrettyPrint. This module exports one default function called printDate(). How can a developer import and use the printDate() function? A. import printDate() from '/path/DatePrettyPrint.js'; printDate(); B. import printDate from '/path/DatePrettyPrint.js'; printDate(); C. import DatePrettyPrint from '/path/DatePrettyPrint.js'; DatePrettyPrint.printDate(); D. import printDate from '/path/DatePrettyPrint.js'; DatePrettyPrint.printDate(); ANSWER: B. import printDate from '/path/DatePrettyPrint.js';printDate(); Additional Info: Once imported by name, you must call the imported method directly by name. You must call the methods directly or use the * to import all methods. When using the `const` identifier to create an instance of an object, are the properties changeable? ANSWER: Yes. An object declared as `const` can be modified. The `const` fix [Show More]

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