5. [A]. To get a head start, early the next morning the farmer started covering ground quickly because he wanted to get as much land as he could.
[B]. Late in the afternoon, he realized the condition he had to fulfill to get the land was to get back to the starting point by sundown.
[C]. Even though he was tired, he kept going all afternoon because he did not want to miss this once in a lifetime opportunity to gain more wealth.
[D]. There is a story about a wealthy who was once offered all the land he could walk on in a day, provided he come back by sundown to the point where he started.