It was said that a few red dwarfs which were created after the big bang are still existing and is hypothesized to continue to live for years approximately 26
The best way to increase validity of data in an experiment is by performing the experiment numerous times and obtaining measurements and data upon each run of the experiment.
C. If your hypothesis is proven then it eventually becomes true. The exact definition for scientific theory is an explanation that can be proved with repeated explanation.
I'm not exactly sure what specifically you are asking for in relationship to balancing equations, but I have some examples with working out so you can examine them and try to go through the steps with them.
Hope this helps! <3