what to put for box 1e cost basis - inherited stock in 2020 sold some some in 2022

[alpaca cats]

hello , I inherited stock in 2020 and sold some in 2022. I had turbo tax auto import from computershare.  turbo tax is asking for box 1e cost basis.. what do i put in here? On the 1099b it was blank. Do i have to figure out the price it was  the day when i inherited the stock or do i leave it at zero? also the sales section was auto selected as unkown term not reported , is that correct or do i need to do longterm not reported (non covered) like the 1099b says?

[Bsch4477]

For date of sale use the drop down menu and choose inherited. The program will automatically make it long term. The cost basis is the value of the asset at the time of the decedent’s death. 

[NCperson]

@alpaca cats  the cost basis is based on the price of the stock on the date the person passed.  Take the closing price on the trading day prior to death and the closing price on the same business day of death (or the first one after the date of death if it occured on a non-trading day).  Average two two figures.

You can normally find historical prices on Yahoo Finance for publically traded firms.