CoachA rock or a mineral is a closed system for a parent isotope and its daughter if, since the moment its clock started, no atom of the parent or of the daughter has entered or left it, other than by the decay of the parent into the daughter.
বইগুলো এখনো বাংলা ভাষায় পাওয়া যায় না — ইংরেজি সংস্করণ দেখানো হচ্ছে।
Earth and Space Sciences · পরিভাষা