There is no requirement for witnesses.
You need two witnesses for a will or codicil to a will. However, if the will or codicil is entirely handwritten (holographic will/codicil), no witnesses are needed. Holographic wills are valid in Ontario, Alberta, New Brunswick, Newfoundland, Quebec, Manitoba and Saskatchewan.
2
To be convicted of treason, prosecutors need at least two eye witnesses. With out any witnesses, a person can not be convicted of treason.
There is no requirement for witnesses to a contract.
Two Witnesses.
Many would say they are. Quite a few witnesses say "They are glad they are" because before they became JWs their brain was full of dirty thoughts etc. and their brains needed washing! In reality, it takes a huge amount of study to become a witness and they enter and get baptized of their own free will. Many highly intelligent people are witnesses. So the objective answer is no they are not.
More details are needed to provide an answer to this question.
Generally two witnesses are sufficient. However, state laws vary so you need to check the laws of your state.
To execute a will, you typically need to sign it in the presence of witnesses who also sign it. It's advisable to consult with an attorney to ensure your will meets all legal requirements in your jurisdiction. After the will is properly executed, store it in a safe place and inform your executor of its location.
Around 135,000 according to the 2015 Yearbook of Jehovah's Witnesses.
Around 4000 according to the 2015 Yearbook of Jehovah's Witnesses.