Answer :

apologiabiology
15 yards=36 inches in a yard times 15=540in
5yds=36 times 5=180 in
so 180 times 540=97,200 in^2

5280 feet in a mile so 5280 times 20= 105,600 feet

105,600>9,200 so 'feet in a 20 mile walk' is more