Alpha emission in an atom reduces its atomic number by two. An alpha particle is actually the nucleus of a helium-4 atom.   In alpha decay, atomic number decreases by 2, and atomic mass decreases by 4.  .   An alpha particle is two protons and two neutrons, this is the same as a helium nucleus.
On most PraxisÂ® tests, each selected-response question answered. correctly is worth one raw point, and your total raw score is the. number of questions answered correctly on the full test. Selected-. response questions are scored by computer.
Standard Score. Standard Score is a set of scores that have the same mean and standard deviation so they can be compared. We will use IQ as our common example to stitch all of this together. Mean is the average of all of the scores and in the very center of a plotted graph of scores (this will be explored later).tandard Score is a set of scores that have the same mean and standard deviation so they can be compared. We will use IQ as our common example to stitch all of this together.