单选题
In the figure above, a square is circumscribed about a circle with a diameter of 20 cm. Points Q, R, S, and T are the midpoints of the square"s sides. What is the total area, in cm2, of the square?
【正确答案】
【答案解析】400
To solve this problem, note that the diameter of the circle is 20 cm, which means that each side of the square is 20 cm. The area of the square is 20cm×20cm, which equals 400cm
2
.