中国猪种的初配年龄一般为()月龄。
A、3~4
B、6~8
C、10~11
D、12~14
参考答案:B
——_____.
——You did? That's great! Congratulations.
A.My wife had a baby last night.
B.Today is my birthday.
C.I just got a pay rise.
D.I failed in my driver's test.
50℃时,下列各溶液中,离子的物质的量浓度关系正确的是
A.pH=4的醋酸中:c(H+)=4.0mol·L-1
B.饱和小苏打溶液中:c(Na+)= c(HCO3-)
C.饱和食盐水中:c(Na+)+ c(H+)= c(Cl-)+c(OH-)
D.pH=12的纯碱溶液中:c(OH-)=1.0×10-2mol·L-1