Identify the type of scientific knowledge represented by each statement.

It is a ok  i know i have a brain functioning well.                                                                                                                                                           

The answer is 3.

A(apex

Each calcium ion has a charge of +2, which can also be written as ca2+. if those ions move out of the neuron and no other ions are moving, the neuron would lose the positive charge associated with those ions and become more negatively charged.