Which of the following is/are true regarding JavaScript and multi-threading/concurrency?

Difference between call() and apply()?

Which is a good reason why JavaScript variables would start with a dollar sign ($)?

Final value of the variable bar in the following code? var foo = 9; bar = 5; (function() { var foo = 2; bar= 1; }()) bar = bar + foo;

Which will correctly check if a variable is undefined in JavaScript?

Which 'if' statement is correctly used to get the size of both 'variable1' and 'variable2' objects? var variable1 = {'name':'theName', 'address':'theAddress','age': '18'} var variable2 = ['theName','theAddress','18']; variable1["name"] = "theName2"; variable1["name"] = "theName3"; variable1["name2"] = "theName4"; variable1["name2"] = "theName5"; Object.size = function(importer) { var exporter = 0, key; for (key in importer) { if (importer.hasOwnProperty(key)) exporter++; } return exporter; };

Which result is returned by the JavaScript operator 'typeof' for the keyword 'null'?

function test(){ return { test:1 }; } alert(typeof test()); What will be the above alert ?

What's the output? var main = function() { var i=2,j=0,k=0,m=1.5,s=0; while(i<=3) { j=1; while(j<=4) { k=1; while(k<=4) { if(k%2!==0) { s=s+i+j+m; k++; } else { k++; m++; } } j=j+2; m++; } i++; m++; } console.log(s); } main();

What's the output? s2 = new String('2 + 2') document.write(eval(s2));

What's the output? var str1 = 'Hi world'; var str = 'Apples are round, and apples are juicy'; var sliced = str.slice(5, -2); var text =`Apple \nJuice` var raw_text = String.raw`Apple \nJuice` console.log(str1.valueOf()); console.log(raw_text) console.log(sliced); console.log(text)