Answer: hey nice to see you again, the answer is B. Microscopes allowed scientists to see the cells.
Explanation:
Black hole, or a singularity contained within an event horizon through which no light can escape.
The element with the lowest ionization energy is CESIUM, CS.
Ionization energy is the energy required to remove the most loosely bound electron in an atom of an element. The higher the number of shells in an atom of an element, the lower the ionization energy that will be required to remove the valence electron.
If the sun was not there the earth would travel in a straight line
