Answer:
Reflection involves a change in direction of waves when they bounce off a barrier. Refraction of waves involves a change in the direction of waves as they pass from one medium to another.
Answer:
The helicopter uses 35 gallons to fly for 5 hours.
Explanation:
The amount of gas that a helicopter uses for flying varies directly proportional to the number of hours spent flying.
g ∝ T
where g represents amount of gas and T time of flight.
Then,

The helicopter files 4 hours and uses 28 gallons of fuel.
Here, g₁= 28 gallons, T₁=4 hours
g₂=?, T₂=5 hours.


⇒28×5= g₂×4
⇒ g₂×4=28×5

gallons
The helicopter uses 35 gallons to fly for 5 hours.
Answer:
In most materials, atoms are arranged in such a way that the magnetic orientation of one electron cancels out the orientation of another
The answer to this question is False.