单选题 The square root of 800 is between which of the following integers?
A. 21 and 25
B. 24 and 28
C. 27 and 31
D. 30 and 34
E. 33 and 37

【正确答案】 C

【答案解析】The best solution here is to plug in the numbers from the answers until you find the range that works. 21×21=441, 24×24=576, 25×25=625, 27×27=729, 28×28=784, 30×30=900... and we do not need to determine the square of 31 to know that the square root of 800 is between 27 and 31.