Question

scientists have dated sharp-edged flakes of stone found in the fine-grained sediments of a dry riverbed in the afar region of ethiopia to between 2.52 and 2.60 million years ago, pushing back by more than 150,000 years the earliest date when it is known that humans made stone tools.

Answer 1

Newton's second law of motionpertains to the behavior of objects for which all existing forces are not balanced. The second law states that the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object.