Gifted land

In 2007 my mother gave me 10 acres that she and my dad purchased in 1965, in Arkansas. My mother passed away in 2013. I sold the 10 acres on January 27, 2020. The land is undeveloped. Price of land from 2007 to present day hasn't changed due to location and town it is located. (This is information I received when calling a real estate agent in the town land is located.) My questions are how do I declare this on 2020 taxes and how to figure any taxes I will have to pay. Also, will this add to my gross income in 2020, putting me in a much higher tax bracket.