A:to prefer; went
B:preferring; had gone
C:preferred; going
D:preferring; and went
已知x,y为实数,且x-1+3y-22=0,则x-y的值为( )
5×8____6×7 8×8+8____8×9
蛙的神经元内、外Na+浓度分别是15 mmol/L和120 mmol/L。在膜电位由内负外正转变为内正外负过程中有Na+流入细胞,膜电位恢复过程中有Na+排出细胞。下列判断正确的是 ( )