The answer is geological pick.
Answer: Layer a is 500 million years old.
Explanation:
Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
When the fish is put into fresh water, suddenly the concentration around them is very low and the water potential is extremely high. Water will now move from the relatively high water potential in the water to the relatively low water potential in the cells, the cells start to burst and the fish dies.
The nurse should anticipate the use of antiviral comination in the management of this patient ( <span>peginterferon alfa-2a and </span>ribavirin). This will help
reduce further damage to the liver. A repeat test should be conducted to
indicate whether the virus is cleared.
