Explain why dead or cliseased trees can serve as a food source for some
birds.

Dead or diseased trees can serve as a food source for some birds because there are some insects which feed on these dead trees and these insects are eaten by some birds. The body of insects is made of protein so it is a good food for birds. The insects which lived in the dead and diseased trees and feed on it are termites and bugs. Termites are also known as white ants. They feed on dead bodies of plants.

answer: 45

explanationyou have to add as well to be it could be

hypoxemia refers to a below usual concentration of oxygen in the blood, mainly in the arteries. hypoxemia is an indication of an issue associated with circulation or breathing and may lead to various symptoms like shortness of breath.  

the condition is identified by determining the level of oxygen in the blood sample obtained from an artery. it can also be predicted by determining the oxygen saturation of the blood with the application of a pulse oximeter.  

the normal arterial oxygen is about 75 to 100 mm hg. the values underneath 60 mm hg is generally considered with the requirement for supplemental oxygen. the normal pulse oximeter readings generally range between 95 to 100 percent. the values under 90 percent are regarded as low.  

in the given case, the oxygen saturation is measured at 93 percent, hence, there is no need to administer oxygen, that is, one should withhold oxygen.