The prevalence rate of a disease refers to the number of people in a population that are affected by a particular disease. The only two reasons why the number of this set of people will decrease is if a cure is found for the disease or if those affected are dying.
Cure or death will reduce the prevalence rate.<span />
Answer:
a
Explanation:
Tidal volume (TV) is the volume of oxygen that enters the lungs (inspiration) through normal breathing. It is measured per kg of body mass.
It is also measurement applied by a ventilator machine. The machine delivers oxygen and the amount delivered is calculated as tidal volume.
'Remaining in the lungs after forced expiration' is called Inspiratory Reserve Volume (IRV)
'Forcibly expelled after normal expiration' is called Expiratory Reserve Volume (ERV)
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.
