When something is periodic, it means that there are repeating patterns. Explain, using examples, why the table of elements is called a periodic table of the elements.

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.

your answer is c) plasma

~*"auba14"*~

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.