2.10以内所有质数的和是( )
A. | 16 | B. | 17 | C. | 18 | D. | 20 |
1.4、5和8三个数的最小公倍数是( )
A. | 4 | B. | 8 | C. | 40 | D. | 160 |
20.一根绳子长$\frac{73}{100}$米,用去$\frac{1}{100}$米,还剩( )米.
A. | $\frac{18}{25}$ | B. | 99% | C. | $\frac{99}{100}$ |
19.5.2499保留一位小数是( )
0 157976 157984 157990 157994 158000 158002 158006 158012 158014 158020 158026 158030 158032 158036 158042 158044 158050 158054 158056 158060 158062 158066 158068 158070 158071 158072 158074 158075 158076 158078 158080 158084 158086 158090 158092 158096 158102 158104 158110 158114 158116 158120 158126 158132 158134 158140 158144 158146 158152 158156 158162 158170 199269
A. | 5.2 | B. | 5.3 | C. | 5.20 |