Answer:
I and III only
Explanation:
Crop rotation is a farm practice that involves cultivating different species of crops on the same land at different seasons. In other words, the different crops are rotated. Crop rotation is done for various reasons including; improvement of soil fertility, pest and disease control etc.
In this case, a crop rotation of various grains and legumes would be an appropriate solution for the following problems:
- The nutrients in the soil on a farm are being depleted: Legumes are known to be rich in nitrogen and hence add nitrogen to the soil due to the nitrogen-fixing microbes in their roots. Hence, rotating between grains and legumes can help return the depleted nutrients (by grains) to the soil.
- A particular kind of pest is infesting the soil on a farm: Most pests are usually crop-specific, hence, planting only one type of crop can make that soil be infested with a particular kind of pest. However, rotating between crops such as grains and legumes can make a particular pests become scarce or less populated.
The human body comprises of more than 600 muscles differentiated in three classifications, and all are under the control of the nervous system. The activities like picking up a dropped pen or leaning over incorporate the combined effort of various muscle groups.
The alert mind relays this instruction to the central nervous system that conducts it in the form of electrical impulses. These are then mediated via the somatic segment of the peripheral nervous system to the nerves accountable for monitoring the essential muscles.
When the signals arrive, a chemical known as acetylcholine gets discharged from the nerve terminals, activating the membranes of muscle fibers and making them to contract. The receptors present in the muscles provide the brain with the instruction regarding the movement and position of the body, the brain monitors the contraction of skeletal muscles.
The particles that make up matter are the atoms.
Atoms do not change during a chemical change. They do not either during a physical change.
During a chemical change molecules change but not the atoms. The atoms separate from the original molecules and form new molecules. Then moleculas change but atoms remain being the same before and after the chemical change.
For example, atoms of oxygen in molecules of O2 combine with atoms of hydrogen in molecules of H2 and they form the molecules of water H2O.
The atoms of O in O2 are the same atoms of O in H2O and the atoms of H in H2 are the same atoms of H in H2O. The molecules changed, from H2 and O2 to H2O, but the atoms are the same.
Un iceberg is una gran masa de hielo. Estan locados en el<span>Atlántico Norte y las aguas que rodean la Antártida.</span>
