JavaScript-easy-level

(https://hh.ru/applicant/skills/674/verification_methods?rank=1&kind=theory)

1. What is the data type of the variable let empty = []?
   -> array

2. Which option incorrectly describes the global scope in JavaScript?
   -> Global variables can be declared inside a function

3. What does typeof null return?
   -> "object"

4. What does typeof “5” return?
   -> "string"

5. You are developing an application that processes user input. You need to:

• Execute the code at least once before checking the condition.
• Keep asking the user for data until they enter a valid value.
• Handle a dynamically changing condition.
  Which flow control statement is best to use?
  -> do-while

5. Which statement about functions and their scope is true for this code?

let value = 100;
function first() {
  let value = 200;
  function second() {
    return value;
  }
  return second();
}

-> second will return 200

7. What will the code output?

function createCounter() {
  let count = 0;
  return function() {
    count++;
    console.log(count);
  }
}
const counter = createCounter();
counter();
counter();
 

-> 1 and 2;

8. What will the code output?

console.log([] + []);

-> ""

9. Which array method is used to create a new array by applying a function to each element of the source array?
   -> map

10. What will the code output?

console.log(0 == false);

-> true

index JavaScript-middle-level hh