Answer:
<em>B</em>
Ovulation happens about 14 days before your period starts. If your average menstrual cycle is 28 days, you ovulate around day 14, and your most fertile days are days 12, 13 and 14
The nucleus controls and regulates the activities of the cell (e.g., growth and metabolism) and carries the genes, structures that contain the hereditary information.
Biology is a branch of science that deals with living organisms and their vital processes.
Chemistry is the science that deals with the properties, composition, and structure of substances
Physics is the natural science that studies matter, its motion and behavior through space and time, and the related entities of energy and force
I think the answer is "the older it is"
Reason: I might be wrong but is something (like a shell) gets buried in something (like sand), overtime many things (like dirt, soil, sand, etc.) will be on top of the original. This will make layers. So, the older rock is on the bottom since it has been there for the longest and it gets covered by other stuff (causing the layers).
Hope this helps! :) (If I'm wrong, sorry :( )
Activation energy is required to start a chemical reaction. Activation energy is the energy needed to allow the reactant to react. Activation energy is measured in Joules (J).