is a learning process in which a neutral stimulus becomes associated with an innately meaningful stimulus and acquires the capacity to elicit a similar response.

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

It's important for a woman to know she is pregnant within the first trimester so she won't consume any alcohol or cigarettes which will harm the baby.