Java React Node Diagnostic Assessment

What is the result of console.log(5 + '5')?

• 10

• "55"

• 55

• Error

• "10"

Which of the following statements has block scope?

• var

• global

• let

• none

• static

What does the setTimeout function do?

• Executes a function immediately

• Stops the program for a while

• Executes a function after a certain time

• Declares a non-blocking wait

• Throws an exception

What is the result of this code?

• "Hello" then "World"

• "Hello World"

• "World" then "Hello"

• "World Hello"

• Error

What method converts an object to a JSON string?

• JSON.convert()

• stringifyJSON()

• JSON.stringify()

• JSON.encode()

• objectToJSON()

What is the result of typeof null?

• null

• undefined

• "object"

• "null"

• "undefined"

What operator is used to prevent reassignment of value?

• const

• let

• var

• define

• Object.freeze()

What array method executes a function for each element without returning a new array?

• map

• reduce

• forEach

• filter

• every

How to generate a random integer between 0 and 9?

• Math.random(0, 10)

• Math.round(Math.random() * 10)

• Math.floor(Math.random() * 10)

• randomInt(0, 10)

• parseInt(Math.random() * 10)

What is a closure in JavaScript?

• A function that executes immediately

• A function that remembers its context

• An unnamed function

• An asynchronous function

• An immutable object