—That actor often joins in different activities in Beijing. Do you know ______?
—For 5 years.
A：how soon he will come back
B：how long he has stayed there
C：when he went there
D：when he will come here
某人有耳垂，体细胞的基因组成为Aa，她所产生的卵细胞有几种基因类型（ ）
正方形有____条对称轴，等腰三角形有____条对称轴．
