What is the area of a square field whose diagonal of length 20 m? Choose the correct choice from the following answers.
A) 288	B) 289	C) 200	D) 112	E) 178
d2/2 = (20 * 20)/2= 
<gadget id="calculator">(20 * 20)/2</gadget>
<output>200</output>
200   Answer: 200
<result>C</result>
What is the area of a square field whose diagonal of length 20 m?