List one possible pathway in the flow of blood from the left index finger to the right atrium of the heart?

The deoxygenated blood moves from the superficial digital veins then goes to either radial or ulnar vein. Then blood travels from brachial veins to subclavian vein. From the superior vena cava, it goes to the right atrium of the heart.

Aneutral atom must have the same number of neutrons and protons? no, they must have the same number of protons and electrons

In fact it is not just nuclear fusion and fission that  can  transform  matter  (or mass)into energy. any time  energy  is produced, some small amount of  matter  or mass isconverted into energy.