A:C3H3N
B:C3H5ONS
C:C3H7O2NS
D:C3H3O2NS
如图,在△ABC中,D是∠BAC的平分线上一点,BD⊥AD于D,DE∥AC交AB于E,请说明AE=BE.
34 ×8=
2.5﹣ 12 =
15÷1%=
23 + 34 =
75 × 1021 =
0.3× 56 =
35 ÷ 910 =
1÷ 78 =
6﹣ 67 =
1﹣1× 13 =