What is the data type of the variable userName?

• Number

• Boolean

• String

• Undefined

What happens when the line age = 30; is executed?

• The value of age is updated to 30.

• The program runs without errors.

• A TypeError occurs because age is declared with const.

• The program will ignore the line.

Which of the following correctly explains the line isStudent = false;?

• A new variable is created.

• The boolean value of isStudent is updated.

• A syntax error occurs because let variables cannot be changed.

• false is appended to isStudent.

Why can userName be reassigned but age cannot?

• userName is a const variable, and age is a let variable.

• Both variables can be reassigned.

• userName is declared with let, allowing reassignment, but age is declared with const, making it immutable.

• const only prevents reassignment for numbers, not strings.

Which statement is true about the let and const keywords?

• let allows reassignment, but const does not.

• const is used only for numbers.

• let variables are automatically converted to strings.

• const variables can be reassigned inside a function.

If the user enters "15" in the prompt, what will be the value of userAge immediately after input?

• 15 (as a number)

• "15" (as a string)

• Undefined

• NaN

What will be the value of yearsSinceBirth?

• 2000

• 25

• "25"

• NaN

What will happen if the user enters "12abc" in the prompt?

• nextYearAge will be 13

• nextYearAge will be NaN

• nextYearAge will be 12

• nextYearAge will be "12abc1"

What data type is nextYearAge after execution?

• String

• Boolean

• Number

• Undefined

Which statement correctly explains why we used const for birthYear?

• birthYear will never change, so const is appropriate.

• birthYear can change, but using const makes the code easier to read.

• const is used only for strings, so it's required here.

• We should have used let instead because const is not necessary.