Regarding the statute of limitations on additional assessments of tax by the IRS, determine the application period in each of the following situations. Assume, a calendar year individual with no fraud or substantial omission involved.

A. The income tax return for 2019 was filed on February 19, 2020 but the return contained a material omission (i.e. more than a 25% of gross income) due to the taxpayers negligence.

B. The income tax return for 2019 was filed on February 19, 2020 but the return contained a substantial omission considered to be fraudulent.