Question

d. What is a first day cover?​

Answer 1

Answer:

first-day cover

noun

an envelope bearing a stamp or set of stamps postmarked on their day of issue.

Answer 2

Answer:

A first day of issue cover or first day cover is a postage stamp on a cover, postal card or stamped envelope franked on the first day the issue is authorized for use within the country or territory of the stamp-issuing authority. Sometimes the issue is made from a temporary or permanent foreign or overseas office.