A:isn’t until later this year that
B:is until later this year
C:is until later this year that
D:not until later this year is that
如图,正方形ABCD的边长为4,将一个足够大的直角三角板的直角顶点放于点A处,该三角形板的两条直角边与CD交于点F,与CB延长线交于点E,四边形AECF的面积是( )
25+____=54。