Ecosystems need producers because they are the start of the food chain.
Producers are consumed by first consumers, the second consumers and so on.
Answer:
D geothermal
Geothermal energy is harnessed beneath the Earth's surface.
Answer: d. the wind
Wind is not a land resource. It is the natural movement of air across the earth surface. Wind is also considered as movement of gases present in the atmosphere. The strength and direction of wind can be measured. It is a atmospheric resource. Wind produces as a result of difference in the atmospheric pressure. When a difference in atmospheric pressure exist air moves from region of high pressure to low pressure area. Wind energy is renewable source of energy can be used to produce electrical energy.
In ancient times, people classified plants and animals by use. Like for plants they are being classified as beneficial or harmful. While for animals, they are classified as domestic animals, wild animals, creeping animals, flying animals, and sea animals.