2013年12月18日SAT真题类型：Mathematics > Standard Multiple Choice 数学选择

　　Read the following SAT test question and then click on a button to select your answer.

　　The circle above has center. Given segments of the following lengths, which is the length of the longest one that can be placed entirely inside this circle?

　　(A)

　　(B)

　　(C)

　　(D)

　　(E)

2013年12月18日SAT考试官方每日一题答案：C

解析：Since the radius of the circle is , the diameter of the circle is . In a circle, the diameter is longer than any segment that can be placed entirely inside the circle. Therefore, segments of length or length could not be placed entirely within the circle, and the correct answer is .

　　为大家提供与12月18日SAT真题同类题型的一道题目，供各位考生练习：

　　Four distinct lines lie in a plane, and exactly two of them are parallel. Which of the following could be the number of points where at least two of the lines intersect?

　　. Three

　　. Four

　　. Five

　　(A)only

　　(B)only

　　(C)andonly

　　(D)andonly

　　(E),, and

解析：Since exactly two of the four lines are parallel, the other two lines are not parallel. If the two non-parallel lines intersect at a point that is not on either one of the parallel lines, then the configuration of lines will give a total ofpoints of intersection. (The best way to verify this is by drawing the two parallel lines and then putting in the other two lines.) If, on the other hand, the two non-parallel lines intersect at a point that is on one of the parallel lines, then there will be a total ofpoints of intersection in the figure. (Again, a sketch is the best way to verify this.) Any arrangement of the four lines will again yield eitherorpoints of intersection. Since you can’t obtain four points of intersection, the correct answer isandonly.