JavaScript Functions Quiz

To pass the quiz, you must correctly answer at least 18 of the 20 questions below. # --quizzes-- ## --quiz-- ### --question-- #### --text-- Which of the following is the correct way to declare a function in JavaScript? #### --distractors-- ```js func greet() { console.log("Hello there!"); } ``` --- ```js defineFunction greet() { console.log("Hello there!"); } ``` --- ```js def greet() { console.log("Hello there!"); } ``` #### --answer-- ```js function greet() { console.log("Hello there!"); } ``` ### --question-- #### --text-- What happens when you call (or execute) a function? #### --distractors-- The code inside the function will run and `null` will always be returned. --- Nothing will happen when you call a function. --- A `TypeError` will be thrown and the program will crash. #### --answer-- The code inside the function will run and a value will be returned. ### --question-- #### --text-- Which of the following is the correct way to call a function? #### --distractors-- ```js exampleFunction; ``` --- ```js exampleFunction>>; ``` --- ```js ()exampleFunction(); ``` #### --answer-- ```js exampleFunction(); ``` ### --question-- #### --text-- What is the role of the `return` keyword? #### --distractors-- The `return` keyword will execute the function. --- The `return` keyword will throw a type error. --- The `return` keyword serves no purpose in functions. #### --answer-- The `return` keyword returns a value from the function. ### --question-- #### --text-- Which of the following is a valid function expression? #### --distractors-- ```js expression function getSum(x, y) { return x + y; }; ``` --- ```js getSum: function(x, y) { return x + y; }; ``` --- ```js function = getSum(x, y) { return x + y; }; ``` #### --answer-- ```js const getSum = function(x, y) { return x + y; }; ``` ### --question-- #### --text-- What are function arguments? #### --distractors-- Values that represents the absence of a value. --- Special values that act similar to anonymous functions. --- Placeholder values used inside of the function. #### --answer-- Real values passed to a function when it is called. ### --question-- #### --text-- What are function parameters? #### --distractors-- Floating point values used inside of the function. --- Values passed to a function when it is called. --- Values that represent the intentional absence of the value. #### --answer-- Values listed inside the function definition. ### --question-- #### --text-- What will be logged to the console? ```js const calculateTotal = (amount, taxRate = 0.05) => { return amount + (amount * taxRate); }; console.log(calculateTotal(100)); ``` #### --distractors-- `10` --- `undefined` --- `1` #### --answer-- `105` ### --question-- #### --text-- Which of the following is the correct syntax for an arrow function? #### --distractors-- ```js const sum <<>> (num1, num2) => num1 + num2; ``` --- ```js const sum === (num1, num2) === num1 + num2; ``` --- ```js const sum >=> (num1, num2) => num1 + num2; ``` #### --answer-- ```js const sum = (num1, num2) => num1 + num2; ``` ### --question-- #### --text-- What will be result for the following code? ```js function greet() { const developer = "Jessica"; console.log("Hello there!"); } console.log(developer); ``` #### --distractors-- Nothing will happen and the code will run normally. --- The string `"Hello there!"` will be logged to the console. --- The string `"Hello!"` will be logged to the console. #### --answer-- You will get a reference error because `developer` is not defined globally. ### --question-- #### --text-- When can you omit a set of parentheses around a parameter list for an arrow function? #### --distractors-- You should always omit the parentheses around a parameter list. --- You are never supposed to omit the parentheses for an arrow function. --- You should only omit the parentheses when you are working with multiple parameters. #### --answer-- You should only omit the parentheses when you only have one parameter. ### --question-- #### --text-- When can you omit the curly braces and `return` keyword for an arrow function? #### --distractors-- You should always omit the curly braces and `return` keyword. --- You should never omit the curly braces and `return` keyword. --- When the function body has multiple lines of code. #### --answer-- When the function body consists of a single expression. ### --question-- #### --text-- What will the following function return? ```js function exampleFunction() { return "Hello"; return "World!"; } ``` #### --distractors-- `"World!"` --- `"Hello World!"` --- `undefined` #### --answer-- `"Hello"` ### --question-- #### --text-- Which of the following is the correct way to use default parameters? #### --distractors-- ```js function sum(num1, num2 <<>> 12) { return num1 + num2; } ``` --- ```js function sum(num1, num2 === 12) { return num1 + num2; } ``` --- ```js function sum(num1, num2 >> 12) { return num1 + num2; } ``` #### --answer-- ```js function sum(num1, num2 = 12) { return num1 + num2; } ``` ### --question-- #### --text-- What will be the result for the following code? ```js const developer = "Jessica"; function greet() { console.log("Hello, " + developer); } greet(); ``` #### --distractors-- The string `"Hello, developer"` will be logged to the console. --- An error message will display in the console. --- Nothing will display in the console. #### --answer-- The string `"Hello, Jessica"` will be logged to the console. ### --question-- #### --text-- What happens if you try to remove the curly braces for a regular function? #### --distractors-- An alert box will display on the page with an error. --- The program will crash and not start again. --- Nothing will happen. #### --answer-- You will get a syntax error. ### --question-- #### --text-- What will be the result for the following code? ```js const sum = (num1, num2) => num1 + num2; console.log(sum(0, 0) + 10); ``` #### --distractors-- An error message will display in the console. --- The number `0` will be logged to the console. --- Nothing will be logged to the console. #### --answer-- The number `10` will be logged to the console. ### --question-- #### --text-- What will be the output for the following code? ```js const exampleFunction = (param1, param2) => param1 + param2; console.log(exampleFunction(3, "Something")); ``` #### --distractors-- `null` --- `undefined` --- `3 + "Something"` #### --answer-- `"3Something"` ### --question-- #### --text-- What will be the result for the following code? ```js const sum = (num1, num2) => num1 + num2; console.log(sum(0, 0) + num2); ``` #### --distractors-- An error message saying `num1` is not defined. --- The number `0` will be displayed in the console. --- `undefined` will be displayed in the console. #### --answer-- An error message saying `num2` is not defined. ### --question-- #### --text-- What will be the output for the following code? ```js const divideTwoNumbers = (num1, num2) => num1 / num2; console.log(divideTwoNumbers(3, 0)); ``` #### --distractors-- `Error` --- `0` --- `null` #### --answer-- `Infinity`