those are nucleotides
since all three of them contain deoxyribose (because there's only one hydroxil group) they are DNA nucleotides
the first nucleotide has cytosine as it's nitrogenous base
the second nucleotide has adenine as it's nitrogenous base
the third nucleotide has thymine as it's nitrogenous base
Youngest to oldest would be: 3, 4, 1, 5, 2. Since it's from the bottom, the ones furthest from the bottom would be the youngest at the top. The oldest fossils would be closest to the bottom.
Scientists use radio technology in order to track endangered species. These include radio collars, tags and chips. These devices can then be tracked wither via satellites through GPS technology or by locating the radio waves emitted by these devices using receivers.
These devices have proven very helpful in tracking organisms and monitoring their populations.
Explanation:
The study of how plants, animals, and organisms are spread across the globe over time and space is known as biogeography.
Example of biogeography includes the splitting of Pangea (all the Earth's continents were one large landmass).