Arow of elements on the periodic table is called an

If we represent the solar system on a scale that allows us to walk from the sun to pluto in a few minutes, then a) the planets are microscopic and the stars are millions of miles away. b) the planets are the size of basketballs and the nearest stars are a few miles away. c) the planets are marble size or smaller and the nearest stars are thousands of miles away.

In the diagram, δgef and δhef are congruent. what is the value of x?

What is the thickest layer of earth called?