What physical feature, which lies between two bodies of water, is the norther border to the muslim empire

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

Which anatomical feature would you expect to find in the fossil remains of a nocturnal species?

If the distance between two points on the ground is 10 miles and the distance between the same two points on a map is 4 inches, what is the map scale expressed as a ratio?