10.下列各对数中,互为相反数的是( )
| A. | 2和$\frac{1}{2}$ | B. | -0.5和$\frac{1}{2}$ | C. | -3和$\frac{1}{3}$ | D. | $\frac{1}{2}$和-2 |
7.下列各数中最小的是( )
0 279651 279659 279665 279669 279675 279677 279681 279687 279689 279695 279701 279705 279707 279711 279717 279719 279725 279729 279731 279735 279737 279741 279743 279745 279746 279747 279749 279750 279751 279753 279755 279759 279761 279765 279767 279771 279777 279779 279785 279789 279791 279795 279801 279807 279809 279815 279819 279821 279827 279831 279837 279845 366461
| A. | 23 | B. | -32 | C. | (-3)2 | D. | (-2)3 |