जहाज अपने नीचे समुद्र की गहराई का पता लगाने के लिए ________ का उपयोग करते हैं। - Ships use ________ to find the depth of the ocean beneath them. - Jahaj Apne Niche Samudra Ki Gaharai Ka Pata Lagane Ke Liye ________ Ka Upyog Karte Hain . Gen Science GS in hindi, question answers in hindi pdf questions in hindi, Know About Gen Science GS online test Gen Science GS notes in hindi quiz book