A.1/1200 B.1/3000 C.1/6000 D.1/8400
A.基準(zhǔn)設(shè)計 B.圖形設(shè)計 C.觀測精度設(shè)計 D.已有網(wǎng)的改進(jìn)
A.50MΩ B.20MΩ C.100MΩ D.200MΩ