GIven a value, which three options can a developer use to detect if the value is NaN?
Choose 3 answers !

Refer to the code below?
Let searchString = ' look for this ';
Which two options remove the whitespace from the beginning of searchString?
Choose 2 answers

A developer is creating a simple webpage with a button. When a user clicks this button for the first time, a message is displayed.
The developer wrote the JavaScript code below, but something is missing. The message gets displayed every time a user clicks the button, instead of just the first time.
01 function listen(event) {
02 alert ( 'Hey! I am John Doe') ;
03 button.addEventListener ('click', listen);
Which two code lines make this code work as required?
Choose 2 answers

Refer to the code below:
let o = {
get js() {
let city1 = String("st. Louis");
let city2 = String(" New York");
return {
firstCity: city1.toLowerCase(),
secondCity: city2.toLowerCase(),
}
}
}
What value can a developer expect when referencing o.js.secondCity?

developer wants to use a module named universalContainersLib and them call functions from it.
How should a developer import every function from the module and then call the fuctions foo and bar ?