Envelope
There is no one-word 8-letter palindrome in English, apparently!
The answer is an envelope. It contains a letter.
strength
strength
One example of an 8-letter word that starts with 'f' and ends with 'h' is "freshish."
Multiple
I'm assuming that you mean" ...for a letter with one 8-1/2 x 11 sheet of paper...Your answer, in detail is here:How_much_is_postage_for_a_Christmas_card_from_US_to_UK
typically, 8 bits make up 1 letter.
There is one eight letter word that can be made from these letters: increase.
Hint is't an 8 letter word.... FB game
One is shutting.
strength