Unless there is a rare plate block number, they are not going to vary in price much. Most modern era stamps, those since about 1940, are going to be worth face value. Dealers sell full sheets of many common stamps at less then face value and certainly don't pay that much for them. Still, consult a catalog and find out their value. You might be surprised!
$5 try ebay
That would be Scott Number US 3561-3610. A complete sheet has a catalog value of $36.75
i have a book of Australian stamps from 2006 and it says the mini sheet is worth $2.50
That would be Scott number US 1745-8. A full sheet of these stamps has a catalog value of $21.00.
It will depend on the specific stamp issue. It could be minimal, worth 15 cents postage for each stamp. They may be 50 or 100 stamps to a sheet. There are some very early 15 cent stamps that could be worth many dollars each. Consult a good stamp catalog to identify the stamp and its value.
This is not a sports question
$57.50 (Brookman Catalog)
Scott #US3226 You can purchase a mint copy for about $1.75. A sheet of 20 stamps will cost you $35, you might be able to sell a sheet for about $10 if you can find a dealer that wants them.
17,500.00
That would be Scott number US 2496. A full sheet of these stamps has a catalog value of $44.10.
That would be Scott Number US 1755. A full sheet of these stamps has a catalog value of $40.00.
Scott Number 3330 pictures Billy Mitchell and a Biplane. This 55c stamp was issued in 1998. It has a purchase price of 70 cents used and $2.25 in mint condition.