题目如图,ABABAB为⊙O\odot O⊙O的直径,弦CDCDCD∥ABABAB,过圆心OOO作OE⊥ABOE\bot ABOE⊥AB交CDCDCD于点FFF,交半圆于点EEE,连接ADADAD,若点FFF为OEOEOE的中点,则∠BAD=______.\angle BAD= \_\_\_\_\_\_.∠BAD=______.知识点：切线的判定章节：图形的性质 / 圆
如图,为的直径,弦∥,过圆心作交于点,交半圆于点,连接,若点为的中点,则如图,为的直径,弦∥,过圆心作交于点,交半圆于点,连接,若点为的中点,则如图,为的直径,弦∥,过圆心作交于点,交半圆于点,连接,若点为的中点,则