Which layer confirms that this sample is soil rather than a mineral mixture? a) silt b) clay c) sand d) organic matter

What is a neurotransmitter involved in mood reward, addiction, and motor behaviors?

Arunner is training for an upcoming marathon by running around a 100-m-diameter circular track at constant speed. let a coordinate system have its origin at the center of the circle with the x-axis pointing east and the y-axis north. the runner starts at (x, y) = (50 m, 0 m) and runs 2.5 times around the track in a clockwise direction.

Assume this car is driven off a cliff . how many arrows of force need to be drawn in the free body diagram? assume no air resistance -five -one -three -four