Why have countries agreed to build space tools that must fall safely into the earths atmosphere

Elias is almost correct. he just got it backwards.the correct answer is that it demonstrates elastic potential energy transforming into kinetic energy.

; lc

In any atom of any element, you will find protons and neutrons in the nucleus of any atom 

Following are the  advantages of the parametric equations: 1) they can be used to graph curves that are not functions, like the unit circle.2) the parameter can be used to represent the quantity that is  useful to  provide us with better information about the graph.3)  it is useful to convert between rectangular equations and parametric equations.with specific reference to chemistry,  parametric equations are employ for solving hydrogen and hydrogen-like ions, quantum mechanically. herein, cartesian coordinates are converted in spherical polar coordinates. the solution obtained, when plotted on spherical polar graph paper, provides visualization of atomic orbital such as s,p,d and f.