Carry all first-class mail between u. s. cities located more than a certain distance apart, and they carry three percent (by value) of the freight shipped throughout the united states.
a. retailers
b. railroads
c. airlines
d. wholesaler

Airlines is an organization that possesses and works numerous planes which are utilized for conveying travelers and merchandise to better places. It conveys all top notch mail between u.s. urban areas found more than a specific separation separated, and they convey three percent of the cargo dispatched all through the unified states.