Answer:A weak immune system
Explanation:
When people get older their immune system becomes weak including the function of the T cells which are cells responsible for fighting infections.
This means it becomes hard to recover from a flue when someone get sick and they are always prone to sickness since their immune system no longer has the power to fight infections.
Answer: This value would be most correctly described as ECOLOGICAL.
Explanation: Ecological refers to anything relating to ecology, the interrelationships of organisms and their environment.
The relationship between primeval forest and indigenous human cultures can be termed ecological. This is because, ecological refers to a relationship between between living organisms and their surrounding environment.
Answer: Parallax
Explanation: Parallax is usually an error which should be avoided when taking measurements. It is the observed difference in the apparent position of an object when viewed from different positions. Motion parallax is the change in the position of an object due to the viewer's movement. In motion parallax, the object distance to the observer's eye seems to affect the relative motion of the object. That is objects close by or near the observer's eye such as mile markers seems to rush or whiz past relative to the observer's direction while distant objects such as hills and mountain tops moves relatively slowly in the opposite direction.
Beauty is in the eye of the beholder means beauty isn't one specific thing and you cannot say something is 100% beautiful because when someone might find beautiful, another person may hate.
So yes, a dark cave can be beautiful to someone as a river might be to another.