Explanation:
Plate tectonics is the idea that the earth's outer solid crust (the lithosphere) is fragmented into a few dozen "plates" that pass relative to each other across the earth's surface, like ice slabs on a lake.
A scientist named Alfred Wegener in 1915 proposed that the continents rammed through ocean basin crust, which would clarify why the shapes of many coastlines (such as South America and Africa) seem to match together like a puzzle.
Average Velocity=Total Distance/Total Time


Answer:
A. aluminum, iron, and silver only
Explanation:
metal elements are great conductors; aluminum, iron, and silver are all metals.
plastic isn't an element, but it still doesn't conduct electricity very well because it isn't a metal
(so I would leave out plastic, because you can only choose 3 max based on the answer choices)
this is a direct current circuit.