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:
How many years back can you get a tax refund? The IRS Statute of Limitations allows you three years from the filing deadline to file your prior year return and claim your refund. For example, the last day to claim your tax refund for the 2013 tax year is April 15, 2017. This is because the deadline date was April 15, 2014. Keep in mind that they also have the same amount of time to audit you and up to ten years to collect any unpaid tax.