What is the difference between /** */ and /********** **********/

Answer 1

Adding more *'s does nothing.
The *'s are simply getting commented out.
From the first /* to the ending */

Answer 2

I think you are trying to do a comment. You do /* to open the comment and */ to close it example:
Some Code
/* your comment goes there */
Some other code

Answer 3

No difference, it's only decoration