var num1 = 10; var num2 = num1; num2 = 20; document.write('num1 = ' + num1 + '<br>'); document.write('num2 = ' + num2 + '<br>'); document.write('<br>'); var arr1 = [10,20,30]; var arr2 = arr1; arr2[1] = 50; document.write("arr1 = " + arr1 + "<br>" ); document.write("arr2 = " + arr2 + "<br>" );