On the reverse side of the coin look at the word "HALF". Just to the left of that word is a narrow "valley" that runs along the edge of the coin. The mint mark is in that "valley". If there is no letter in the valley, the coin was minted in Philadelphia.
In all lower values they have the same value. Is values above MS60 the 1945-S takes a higher value.
The 1945-D is a common coin. In average circulated condition values are $16.00-$18.00. Better circulated coins are $20.00-$25.00.
If you have a Denver minted coin it will have the mintmark D. The location of the mintmark will depend on the date.
It's just a common half dollar no silver spend it
If you mean a 1971-D half dollar, it's just 50 cents.
Not being certain which half dollar you have, I can tell you that there was never an "A" or a "N" mint mark. The letters you should find will be a "D", an "S", an "O", a "P" or a "CC"
The 1963-D Franklin half dollar is the highest mintage of the series, most are valued for the silver at about $6.00.
50 cents.
It will have a D mintmark. '
The '44-D half dollar is a fairly common coin. It's worth around $11 in average condition and closer to $30 if uncirculated.
999,999,999,999,999,999,999,999,999,999,999,999,999,999,999,999,999,999,000
50 cents in a half dollar