The number of possible elements is not known. A very early suggestion made by Elliot Adams in 1911, and based on the arrangement of elements in each horizontal periodic table row, was that elements of atomic weight greater than 256Â± (which would equate to between elements 99 and 100 in modern-day terms) did not exist.
IRS debts can only legally be collected for 10 years, but there are many events that may stop that 10 year clock from running. This is known as tolling the statute of limitations. Events that stop or toll the statute of limitations from running include:
The statute of limitations on how far back the IRS can audit (called the Assessment Statute Expiration Date or ASED) varies depending upon the circumstances of the tax return. In most cases the IRS will not go back more than 3 years unless there is something very wrong with the tax return that was filed.