title: Which parts does two way binding updates?
body: <p>Assume I have the following array in the controller with SortBy model. </p>
  
  <pre><code>var empsColl = [
          { 'firstName': 'Donney', 'gender': 'male', DOB:new Date("November 20, 1978"), salary1:12000, salary2:12000 },
          { 'firstName': 'Obama', 'gender': 'male', DOB: new Date("April 10, 1980"), salary1: 40000, salary2: 40000 },
          { 'firstName': 'Jeb', 'gender': 'male', DOB: new Date("May 20, 1990"), salary1: 120000, salary2: 120000 },
          { 'firstName': 'Xing', 'gender': 'male', DOB: new Date("May 3, 1990"), salary1: 12, salary2: 12 },
          { 'firstName': 'Dillon', 'gender': 'male', DOB: new Date("May 3, 1990"), salary1: 6000, salary2: 6000 }
      ];
      $scope.Employees = empsColl;
      $scope.SortBy = 'firstName';
  </code></pre>
  
  <p>in the view I have used two-way binding in two places one in <code>&lt;select ng-model="SortBy"&gt;</code> and in an expression binding in  <code>&lt;div&gt;{{SortBy}}&lt;/div&gt;</code></p>
  
  <p>I definitely know that model update updates the expression binding part but does it re-updates the selected option in <code>&lt;select&gt;</code>?</p>