Convert these dates to BP dates (using 1950 as "the present.")1843 ± 50 years BC

To convert a date to BP (Before Present) format, we need to calculate the number of years before the reference year, which is usually considered to be 1950.

In this case, we have the date 1843 BC, and we want to convert it to BP using 1950 as the present year.

Step 1: Calculate the number of years between the given date and the reference year.
To do this, subtract the given year from the reference year:

1950 - 1843 = 107

Step 2: Since the given date is in BC (Before Christ), we need to add 1 to the result from Step 1.

107 + 1 = 108

Step 3: Finally, add "BP" after the number to indicate that it is in Before Present format.

Thus, the converted date is 108 BP.

To summarize, to convert a date to BP using 1950 as the present year, subtract the given year from 1950 and add 1 if the given date is BC.