jquery.validationEngine.js dropwdown

Im using jquery.validationEngine.js everything is setup and working fine, however i need to make a change.

I have two dropdown boxes.

Is The Vehicle Imported? [yes, no] What Is The Country Of Origin? [France, Germany, Japan, USA, UK] etc

what i require is that if the car is imported then to show the country of origin, else display nothing.

at the moment i have both fields working on a live form,

                 <label>Is The Vehicle Imported?</label>
                <select class="validate[required] target" name="strLeadData39" id="strLeadData39">
                 <option selected="selected" value="">Please Select</option>
                                <option value="No">No</option>
                                <option value="Yes">Yes</option>
                                </select>

                                 <label>What Is The Country Of Origin?</label>
              <select class="validate[required] target" name="strLeadData40" id="strLeadData40" >
                                <option selected="selected" value="">Please Select</option>
                                <option value="Not Imported">Not Imported</option>
                                <option value="France">France</option>
                                <option value="Germany">Germany</option>
                                <option value="Japan">Japan</option>
                                <option value="Canada">Canada</option>
                                <option value="USA">USA</option>
                                <option value="EU-Other">EU-Other</option>
                                <option value="Other">Other</option>
                      </select> 

How do i complete this.

Thanks