External fertilization in animals usually occurs in water or in damp areas in a process called spawning.
Answer:
Measuring a pencil in meters would be very difficult, as a single meter is much longer than one pencil. Also, measuring a hallway in millimeters would be very difficult considering how small millimeters are in comparison to a hallway. However, if you switch these two then they would work very well.
B - Atomic number. Dmitri Mendeleev organised the table according to atomic weight, however this caused problems with elements such as iodine and tellurium, Iodine has a higher mass, but a lower atomic number. And to make iodine in the same group as similar elements (halogens), Mendeleev had to break his own rules and put it before tellurium in the table. Moseley fixed this problem by ordering the elements according to atomic (proton) number.
Answer:
As the sun's angle changes, (because of the rotation of the earth) the sun slowly begins to shine more or less sunshine slowly. When sunsets and sunrises occur, the color of the sky changes because the sunshine is starting to fade out or in.
I put it in my own words so you don't have to worry about plagiarism :)