Fill in the blanks: 1, (17/9), 2, (1)3, (-800) (-200) (+2000) 4, (3.7)5, (65438+.

Options: 1, B 2, C 3, C 4, B 5, C 6, d.

Three. 1, 5 2, 123 3, 15/8 4, 1004.8 cubic centimeters.

Four. 1，( 1)8 102n+4(2) 1 12(3) 100。

2、 12

3、920

4 2.9 1 (yuan) 5 24

Additional questions: 48%