According to the USPS website, under "Buy Stamps", then "Rate Change", the brown background non-denominated US Flag stamp is $.41.
The US flag is one of the most popular subjects for a Postage Stamp and can be found on dozens of them. The value of each will be dependent upon condition and rarity. You would have to identify the specific stamp to determine the value.
$0.20
39 cents
The US issued a Chester W Nimitz stamp.
If it says US Addresses Only it is good for 32 cents worth of postage. The Make Up stamp is worth 3 cents.
Air mail stamps are good for ordinary postage- your stamp is still worth 7 cents if unused.
That depends on many factors. A stamp is worth its face value for use as postage. If you have something that is old and is rare, it could be worth some money. Today's First Class postage stamps are 44 cents.
The B stamp pictures a stylized eagle. It has a value of 18 cents. You can still use it for 18 cents worth of postage.
Scott #'s 2517-2520 29 cents.
The F series stamps were issued in 1991. The postage stamp has a face value of 29 cents.
Face value.
Which one? There are 30 US stamps printed with Andrew Jackson.
A 28 cent stamp that is unused can always be used as 28 cents worth of postage. If it is used, it probably has a minimal purchase price of fifteen cents from a dealer.