If you are concerned about a refund, and the statute of limitations for filing a claim for refund for the year(s) at issue has not yet expired, you should file Form 1040X, Amended U.S. Individual Income Tax Return, to protect your statute of limitations. File a separate Form 1040X for each year.
The opossum's dental formula is: 5.1.3.4 4.1.3.4 In many mammals the children have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, baby teeth or milk teeth. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont.
From a small number of generalist stem mammals, mammals evolve into a diversity of forms to fill these vacant niches. The earliest mammals had more teeth than humans; the human tooth formula is 2,1,2,3/2,1,2,3 (2 incisors, 1 canine, 2 premolars, and 3 molars in both the upper and lower jaws. The dental formula of an opossum is compared to that of a human in the images below.