Sodium is kept immersed in kerosene because Sodium doesn't react with kerosene.
Explanation:
Owl has the role of the tertiary (third) consumer, in above food web.
The best answer would be:
Osteoarthritis
<span>It is when the person experiences too much weight bearing activities, which may cause the wear and tear breakdown of the joints. This worn bone may be a foreign material when identifying the joint erosion.</span>