Placer deposits form when heavy eroded particles settle out of moving water hot, metal-rich fluids cool below the surface magma cools in underground chambers organic matter is compressed over millions of years

It depends on the surface of the levels. the rougher the surface, the greater is the frictional force. for rougher surfaces, you would need to exert greater force to move the object. the concept is that, you must overcome the frictional force in order to bring the object into motion. this is the reason why we add lubricants to the joints so they could easily move. this answer was on

The correct answer is "b"