สอบถามเรื่องวิธีการทำ List Menu ให้เลือกตาม List Menu แรกที่เลือกไว้

<select name="groupequipment" id="groupequipment" style="width:60mm;font-family:Angsana New;font-size: 15pt;" onchange="this.form.submit();">
				<font face="AngsanaUPC" style="font-size:15pt;"><option value="-">กรุณาเลือกยี่ห้อรถ</option>
				<?
					query("USE measuring_tool");
					$getName=getList("SELECT * FROM type_equipment");
					for($k=0;$k<sizeof($getName);$k++){
						$selected=$_POST[groupequipment]==$getName[$k][TEID] ? "selected=\"selected\"" : "" ;
						?><font face="AngsanaUPC" size="4"><?print("<option value=\"".$getName[$k][TEID]."\" ".$selected.">".$getName[$k][TEDetail]."</option>");?></font><?
					}
				?>
			</select></font>

			<select name="RENo" id="RENo" style="width:60mm;font-family:Angsana New;font-size: 15pt;" onchange="this.form.submit();">
				<font face="AngsanaUPC" style="font-size:15pt;"><option value="-">กรุณาเลือกรหัสอุปกรณ์</option>
				<?
					query("USE measuring_tool");
					$getEquipment=getList("SELECT * FROM equipment WHERE EType = '$_POST[groupequipment]' and EStatusEQ = '2' and EStatus = '1'");
					for($j=0;$j<sizeof($getEquipment);$j++){
						$selected=$_POST[RENo]==$getEquipment[$j][ENo] ? "selected=\"selected\"" : "" ;
						?><font face="AngsanaUPC" size="4"><?print("<option value=\"".$getEquipment[$j][ENo]."\" ".$selected.">".$getEquipment[$j][ENo]."</option>");?></font><?
					}
				?>
			</select>