I would say D, because you need to start with nothing to measure the different sizes as they start to grow. hope this helps!
A compound machine is that which is composed of two or more simple machines. Simple machines come in 6 basic types: (1) wheel and axle, (2) inclined plane, (3) wedge, (4) pulley, (5) screw, and (6) lever. Among the choices given above, the compound machine is the can opener for it is a combination of a wedge and a lever.
Answer:
Abrasion
Explanation:
Here's an example, strong winds on a beach where some rocks are cause the sand to rub against the rocks, causing heat and eventually crack and destroy the rock. The ice of glaciers can also break down rocks when rocks are frozen inside it, and that's cooling.
