Which of the following observations indicates that an atom has neutrons?

A. Some uncharged particles are scattered by a beryllium atom when it hits a gold foil.
B. Some uncharged particles bounce back from a gold foil when it is bombarded with alpha particles.
C. A radiation with neutral particles is emitted when alpha particles strike beryllium atoms.
D. A radiation which attracts electrons is produced when a beryllium atom is bombarded with alpha particles.

I’m really not sure what’s the answer. sorry

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.