Which statement best explains why sensors (or senses) are necessary to produce a change in behavior? A.
Organisms cannot sense stimuli without a central nervous system.
B.
Stimuli must be sensed in order to produce a response.
C.
Stimuli must be responded to in order to be sensed.
D.
Organisms cannot respond to stimuli without a central nervous system.

On a frictionless air track, a blue glider with mass 0.200 kg is moving to the right with a speed of 8.00 m/s. it strikes a red glider that has mass 0.600 kg and that is initially at rest. after the collision, the blue glider is moving to the left with a speed of 3.00 m/s.(a) what are the magnitude and direction of the velocity of the red glider after the collision? (b) is this collision elastic?