How to use Different Button in bootstrap Form

I have used Bootstrap and created form.my form Looks like

<form action="default_results.php"   method="post" class="calculator"  name="frmCalculator">  

I have used this code in the beginning of my code and end of the page I have used three button Looks like

              <div class="row">

                            <button id="button2" class="dont-compare shadow-inset" value="reset" >
                                    Reset</button>
                            <button id="button3" data-toggle="pop" class="dont-compare shadow-inset" class="update" >
                                    Update MI</button>
                            <button id="Button4"  class="dont-compare shadow-inset" class="calculator" >
                                    Calculate Scenarios</button>
              </div>

I have another page its called default_ results.php page. I want to load that page when I click Calculate Scenarios button.I have used href tag for that button. But that three button also load default_results page.

How to set particular button? please any idea about it?