题目

Rt△ABC中，∠C=90°，AC=2，BC=4，如果以点A为圆心，AC为半径作⊙A，那么斜边中点D与⊙A的位置关系是（ ）A. 点D在⊙A外 B. 点D在⊙A上 C. 点D在⊙A内 D. 无法确定 答案：【答案】A【解析】试题解析：根据勾股定理求得斜边 则 ∴点在圆外.故选A. South Korean first female president, Park Geun-hye (朴槿惠) promised __________ her best to serve people. A. do                B. doing                      C. did                   D. to do