A mechanical wave must have a medium.
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♥<em>A.W.E.<u>S.W.A.N.</u></em>♥
Answer:

Explanation:
The time taken by the light to travel a given distance is defined as:

Here c is obviously the speed of light. Now we convert the average distance form Venus to Earth to meters:

Finally, we calculate the minutes taken by the light to travel from Venus to Earth:

m x h x 9.8 m/s squared
70 kg x 3 m x 9.8 m/s squared= 2058 Joules
Answer:
2649600 Joules
Explanation:
Efficiency = 40%
m = Mass of air = 92000 kg
v = Velocity of wind = 12 m/s
Kinetic energy is given by

The kinetic energy of the wind is 6624000 Joules
The wind turbine extracts 40% of the kinetic energy of the wind

The energy extracted by the turbine every second is 2649600 Joules