Metalworking began a. during the Upper Paleolithic period. b. with the introductions of Bronze, an alloy, or mixture of tin and copper, changed the peoples of Europe. c. out of a need for stronger weaponry to used against the increasingly aggressive Vikings. d. with, and because of, all of the above circumstances. Please select the best answer from the choices provided A B C D

the role of the microscope world in creating new materials .

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?