D. Political map would be it
Answer: 4500 metres
Explanation:
Echo is a reflection of sound wave. It is the sound heard after it has been reflected off the surface of a wall or cliff.
Time = 6 seconds
Speed of sound in water = 1500m/s
distance =?
From the relationship ;
Speed = distance / time
Distance = speed * time
Distance = 1500 * 6 = 9000 metres
Distance here represents the total distance traveled by the pulse that is distance to the seafloor and back to the surface.
Therefore the depth of the water is given by;
Depth = distance / 2
Depth = 9000 / 2 = 4500metres.
Answer:
pollution
Explanation:
The natural energy is the energy that is considered to be renewable energy. This type of energy has been becoming more and more popular in the past few decades, especially in the more developed countries. The main reason for the raise in popularity has been the environmental concerns.
The natural energy is in general environmental friendly, which is a major asset for it, especially at present with all the efforts to reduce the pollution. The energy that comes from the sunlight, from the water, the wind etc. fall into this category. They don't cause nay pollution, or it s very small, so lot has been invested in this type of energy production.
The problem is that the price and efficiency of this energy is still not able to pair the ones of the fossil fuels, but with the development of the technology there is every chance that that issue will be solved very quickly.
