A:﹣NH2﹣CO﹣
B:﹣NO﹣CH﹣
C:﹣NH﹣CO﹣
D:﹣NO﹣CH2﹣
⑴____hair hear
⑵____there where
⑶____chair here
⑷____pear bear
17×3=____
100÷50=____
23×4=____
500÷10=____
160÷40=____
640÷80=____
27×3=____
810÷90=____