A tug boat is lugging a cable of 8km long which has signal receivers on it. The receivers are evenly distributed with a distance of 12.5m between each of em. The boat keeps moving forward and every 50 meters, it fires a signal wave downwards the seabed. The signal is then bounced back and received by receivers on the cable. The middle point between the position where the signal was fired and the receiver picking up this very signal is called TMP. Therefore, one fired signal has 1 TMP per receiver but there're so many receivers on the cable. So one fired signal can have many TMP's. But one TMP may be corresponded to many signal/receiver pair as the boat is moving and it keeps firing. Question is how many fold (signal/receiver pair) for one TMP?