Answer:
The correct answer is option d.
Explanation:
Chemical cycling illustrates the systems of concurrent circulation of elements between other states, compounds, and substances, and then return to their original state, which takes place in space, and on many objects in space comprising the Earth.
Chemical cycling of the nutrients (inorganic) is needed to maintain the conservation of nutrients on Earth. The chemical cycling of nutrients in a natural system requires a pool for the elements, the activities done by human beings, the biotic community and its food chains, and an exchange pool from which producers extract their nutrients. All the mentioned factors are associated with affecting a chemical cycling in exception to the input of geothermal energy.
Answer:
D
Explanation:
The gradient in bed load is mostly made up mostly of gravels and sands, broken down versions of larger boulders and rocks, which are most commonly found in mountainous areas. Streams with low gradients cannot carry bed load down stream because it moves slowly and without much force. Gravels and sands couldn't move downstream because the water flow isn't strong enough to move them or to keep them in motion.
Answer: blood travels from the heart through arteries and blood travels to the heart through the veins.
I hope this helps
