Select Problem

["The_FedEx_Guy"]

Hi all,
 I'm using a form that has a selectbox(B_R) which needs to control what is 
displayed in two other selectboxes (minPrice and maxPrice). I haev tried some 
methods online, and rehashing code but to no luck.

 I have the searchbox.php called into index.php 
 The contents of searchbox.php is:
 <form action="search_results.php" method="post" name="form1" id="form1">
       <table width="100%" border="0" cellpadding="0" cellspacing="0">
         <tr>
           <td class="style1">Type:</td>
         </tr>
         <tr>
           <td class="style1"><label>
           <select name="B_R" class="style1" id="B_R" >
             <option value="BUY">For Sale</option>
             <option value="LET">To Let</option>
           </select>
           </label></td>
         </tr>
         <tr>
           <td width="122" class="style1">Location:</td>
         </tr>
         <tr>
           <td><input name="q" type="text" class="style1" id="q"></td>
         </tr>
         <tr>
           <td class="style1">Property Type:</td>
         </tr>
         <tr>
           <td><select name="PropType" class="style1" id="PropType">
             <option value="0">Any</option>
             <option value="Houses">Houses</option>
             <option value="Flats/Apartments">Flats/Apartments</option>
             <option value="Bungalows">Bungalows</option>
             <option value="Commercial">Commercial</option>
                     </select></td>
         </tr>
         <tr>
           <td class="style1">Bedrooms:</td>
         </tr>
         <tr>
           <td><select name="NoBeds" class="style1" id="NoBeds">
             <option value="0">Any</option>
             <option value="1">1</option>
             <option value="2">2</option>
             <option value="3">3</option>
             <option value="4">4</option>
             <option value="5">5</option>
             <option value="6">6</option>
           </select></td>
         </tr>
         <tr>
           <td class="style1">Min Price &pound;:</td>
         </tr>
         <tr>
           <td><select name="minPrice" class="style1" id="minPrice">
             <option value="0">Any</option>
             <option value="25000">&pound;25.000</option>
             <option value="50000">&pound;50.000</option>
             <option value="100000">&pound;100.000</option>
             <option value="150000">&pound;150.000</option>
             <option value="200000">&pound;200.000</option>
             <option value="250000">&pound;250.000</option>
             <option value="300000">&pound;300.000</option>
             <option value="350000">&pound;350.000</option>
             <option value="400000">&pound;400.000</option>
             <option value="450000">&pound;450.000</option>
             <option value="600000">&pound;600.000</option>
             <option value="900000">&pound;900.000</option>
                               </select></td>
         </tr>
         <tr>
           <td class="style1">Max Price &pound;:</td>
         </tr>
         <tr>
           <td><select name="maxPrice" class="style1" id="maxPrice">
             <option value="0">Any</option>
             <option value="25000">&pound;25.000</option>
             <option value="50000">&pound;50.000</option>
             <option value="100000">&pound;100.000</option>
             <option value="150000">&pound;150.000</option>
             <option value="200000">&pound;200.000</option>
             <option value="250000">&pound;250.000</option>
             <option value="300000">&pound;300.000</option>
             <option value="350000">&pound;350.000</option>
             <option value="400000">&pound;400.000</option>
             <option value="450000">&pound;450.000</option>
             <option value="600000">&pound;600.000</option>
             <option value="900000">&pound;900.000</option>
                               </select></td>