Q--Do mail carriers need multiple uniforms?
A--My step-by-step reasoning: Mail carriers work throughout the year independent of the weather. Mail carriers must often leave their vehicle in various weather conditions.
So, the answer is yes.

Q--Did Jack Dempsey ever witness Conor McGregor's fights?
A--My step-by-step reasoning: Jack Dempsey died in 1983. Conor McGregor's first MMA fight was in 2008.
So, the answer is no.

Q--Would Robert Wadlow tower over a German Shepherd?
A--My step-by-step reasoning: German Shepherds have a height between 22 and 26 inches. Robert Wadlow was the tallest man ever, reaching a height of 8 ft 11.1 inches at his death.
So, the answer is yes.

Q--Would a packed Wembley stadium be likely to have a descendant of the Mongols inside?
A--
My step-by-step reasoning: Wembley stadium has a capacity of 90,000 people. The Mongols were an ethnic group that dominated the 13th and 14th centuries. Genghis Khan was the founder of the Mongol Empire. Geneticists have determined that 1 in every 200 men are descended from Genghis Khan.
So, the answer is yes.