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Output Basics
Preview — 3 of 10 questions
What is the output of this code?
javascript
console.log(x);
var x = 5;
console.log(x);AReferenceError then 5
Bundefined then 5
C5 then 5
Dnull then 5
What does this expression evaluate to?
javascript
console.log(typeof null);A"null"
B"undefined"
C"object"
D"boolean"
What is logged to the console?
javascript
console.log(1 + "2" + 3);A6
B"123"
C"15"
DNaN
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