Answer: The ocean is one of Earth's most valuable natural resources. It provides food in the form of fish and shellfish about 200 billion pounds are caught each year. It's used for transportation both travel and shipping. It provides a treasured source of recreation for humans
Explanation:
The answer is the fourth one: Decrease in the fertility of the soil. If you just do crop rotation (harvesting a crop then planting the same type on the same soil) for many years, the soil just loses fertility because of so many of the same plants just using and depleting the fertility from the soil, making the soil less nutritious for the crops.
Answer:
Once an organism is beyond a certain size, it cannot get essential molecules into and out of cells solely by diffusion. Diffusion is limited by the surface area to volume ratio of the organism.
Answer: B. There was no sunlight.
Explanation:
Because sand cannot hold heat, it needs a constant source of energy to stay warm (the sun). so during the night when the sun is not shining, the sand loses all its heat, making the sand cooler than it was in the day.