Which five lakes form a natural border between canada and the u. s?

Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

#4.) describe the most likely weather conditions at indiana / ohio boarder. also could someone double check my other answers? i'd really appreciate it

Wegeners theory of continental drift states that the continents have changed throughout history while the theory of plate tectonics