HELP LAST ATTEMPT to ( get marked brainliest show work !

Answer:
D
Step-by-step explanation:
First student's calculation :
Area = 3*20*20 = 1200 sq. yds
Second student's calculation:
Area = 3.14 * 20 * 20 = 1256 sq. yds
Difference = 1256 - 1200 = 56 sq yds
Answer is D