Refraction is caused by any wave crossing the boundary out of one substance and into another one. The two different substances may be no more than two parcels of air at different temperatures.
Hey Friends
The answer to this question would be C
Hope i helped
~Katie
Answer:
The driver hits the stationery dog because the applied force is less than required force
Explanation:
Kinetic energy will be given by
where m is the mass of the vehicle and v is the speed/velocity of the vehicle.
Substituting 800 Kg for m and 20 m/s for v we obtain

Frictional force by vehicle pads is given by
where d is the distance moved
Substituting 160000 for KE and 50 m for d we obtain

Therefore, the vehicle hits the dog since the required force is 3200N but the driver applied only 2000 N
99% of the earth´s atmosphere by mass is made up of only these elements: Nitrogen and oxygen.
Answer: B) Nitrogen and oxygen.