Answer:
After C14, Uranium238 is most widely used mineral in geological or archaeological dating.
Explanation:
U238 is generally used to date the rock materials, to know the age. As we know the half-life of U238, it is easy to identify the age of the materials containing uranium 238. It can be called as absolute dating method as it determines the exact age of the uranium contained material. It is a type of radiometric dating.
I think the answer is 1, change ammonia into nitrates.
An example of vesiscle-mediated transport would be cell secretion by exocytosis.
The reason why this would be an example of vesicle-mediated transport is because all the other types of transport listed here are not something you would call vesicle-transport; the substances don't really get transported in vesicles. This is different in exocytosis where the compounds gets packaged into vesicles.
Answer: D volcanic eruption