Quiz will ask 20 randomly selected questions with allotted time of . You can take the quiz more than once. Once you submit the quiz, you can review how you have done, the correct the answers for each questions and the explanation for the correct the answer.
10 Modules
Which of the following statements about 'var', 'let', and 'const' are correct?
Variables declared with 'var' are function-scoped.
Variables declared with 'let' are block-scoped.
Variables declared with 'const' can be reassigned.
Variables declared with 'const' must be initialized at the time of declaration.
What will be the output of the following code?
var x = 10;
if (true) {
var x = 20;
}
console.log(x);
10
20
ReferenceError
undefined
What will be the output of the following code?
let a = 1;
if (true) {
let a = 2;
}
console.log(a);
1
2
ReferenceError
undefined
Which of the following are true regarding hoisting in JavaScript?
'var' declarations are hoisted to the top of their function scope.
'let' and 'const' declarations are hoisted but not initialized.
Variables declared with 'let' can be accessed before their declaration.
Functions declared with 'var' can be invoked before their declaration.
What will be the output of the following code?
const obj = { prop: 1 };
obj.prop = 2;
console.log(obj.prop);
1
2
ReferenceError
TypeError
10 Modules