题目

— What’s wrong with Jane? — A call from her mother ______ the attack of homesickness. A．sent out   B．sent off  C．set out   D．set off 答案：D如图所示，已知△ABC内接于⊙O，BD为直径，AB=AC，∠BOC=120°．（1）求证：△ABC为等边三角形；（2）求∠CAD的度数．